Technique Archive

Slinging IFR

Tuesday, June 30th, 2015

Flying helicopters IFR with a sling load presents unique challenges, requiring specific skills of the pilot.  One must obviously be able to control the helicopter without any outside visual references. Less obvious, one must also be able to correctly interpret the instruments, which reflect both the behavior of the load and the orientation of the helicopter. A Class B external load (sling load) is one that is free of the earth’s surface and is attached to the helicopter by a synthetic or wire line. The pilot is “flying” both the helicopter and the load, which at times can seem to have a mind of its own.

Today slinging IFR is not a common practice, though there was a time on the North Slope of Alaska where it was employed regularly. I thought it might be interesting to look at this operation in some detail.

 

An AW139 lifts off for an external load training flight out of Deadhorse Alaska.  Photo by Dan Adams

An AW139 lifts off for an external load training flight out of Deadhorse Alaska. Photo by Dan Adams

.

Controlling the sling load

Normally one can see the external load, and make the necessary corrections. Lateral swinging is more common than a fore-aft motion or a circular motion, so we will focus on that. A quick lateral cyclic input towards the load, just as it reaches its apex, moves the aircraft over the load neutralizing its motion. You are essentially moving the aircraft over the load after it has swung out to the side. This dampens the movement of the load and stabilizes it. However, when flying IFR the instruments must be used to indicate the loads’ position and movement. The best way to learn how the instruments reflect the movements of the load is during VFR flight, when the load and gauges can be seen together.

Flying IFR with a sling it is important not to make corrections reflecting the gauges as one normally would, but instead understand exactly what the load is doing beneath you. The attitude indicator reflects rhythmic changes in bank angle from the load tugging the helicopter laterally side to side, as does the ball in the inclinometer. The inclinometer is used to indicate when and how much lateral cyclic input is necessary for a correction, though there is a natural lag. The load will reach its apex prior to the inclinometer, and the pilot must compensate for this natural lag. When the ball starts to swing out of center to the right and is about half way from its apex, the load is almost at its apex to the left, the pilot then uses left lateral cyclic as a correction. The rhythmic oscillations in the attitude indicator and inclinometer reflect the movements of the load, and the average of these movements are the actual orientation of the aircraft.  The pilot learns to mentally average these oscillations in order to control the pitch, roll, and yaw of the aircraft itself.

“An ounce of prevention is worth a pound of cure”, so one learns to make flight control inputs very smoothly so as to not aggravate the load. Turns are initiated slowly, and half standard rate turns are sometimes prudent.

Determining cruise airspeed

Another consideration is determining the target airspeed at which to fly.  This must be greater than Vmini (minimum IFR speed) and less than the loads effective Vne. While the aircraft will have an external load airspeed limitation, this may not be possible if the load is unstable at a lower speed. Many loads cannot be flown at the external load Vne, and the effective Vne must be determined. As the pilot slowly accelerates during takeoff, the load is carefully watched prior to IMC to determine what airspeed above Vmini the load can be flown at. Once that airspeed is determined, it is maintained for the entire flight.

Should the load show signs of instability below Vmini or only slightly above so as to not provide a safe and adequate airspeed window, the takeoff is aborted while still VMC.

One should be sure of a load’s stability and capability at a safe airspeed prior to IMC, and one should only fly known loads in IFR or at night. A known load is one that is similar to one previously flown during the day. The load characteristics are predictable and stable.

Autopilots and external load operations

Autopilots and external loads don’t usually mix, and many Rotorcraft Flight Manuals prohibit autopilot coupling during external load operations. The autopilot can be too abrupt in pitch attitude and roll, particularly when initiating and terminating turns. A pilot can make changes with a more gentle touch; such as slowly entering a half-standard rate turn when necessary. The autopilot can be used for stability augmentation; it just shouldn’t be coupled to the flight director directly controlling the aircraft.

Horizontal and vertical situational awareness

Class B sling loads can be jettisoned, either intentionally or unintentionally. The hook release is typically electric and controlled by the pilot. Under normal operation the load is released once it has been placed gently on the ground; however, in the case of an emergency the pilot may opt to release it in flight. Due to the possibility of the load being released in flight, persons or property are never overflown. This requires horizontal situational awareness; easy enough VFR, but IFR is another matter. Fortunately, the North Slope of Alaska provides assurance due to its desolate nature.

Vertical situational awareness must also be considered, not just for the helicopter but also for the load hanging underneath. With the typical 25 to 50’ line, the altitude of the load isn’t a factor in cruise flight; however, during the instrument approach it must be considered.

The Instrument Approach

As much fun controlling the helicopter and load may be in IFR conditions, eventually we do need to land. For that we need to fly an instrument approach. Let’s stick with the North Slope of Alaska, using the Deadhorse (PASC) ILS 05 as an example, using a little simple math.

A load 5 feet high hanging on a 50 foot line would require a 55 foot adjustment factor to the decision altitude. For the Deadhorse ILS, this means increasing the decision altitude of 267 feet to 322 feet, and ALS conditional altitude of 167 feet to 222 feet. It would also be prudent to include this 55 foot altitude adjustment into your preflight IFR planning.

Final Thoughts

While flying slings IFR is no longer common, the training for IFR slings still occurs. Having the skill and confidence to be able to fly a sling IFR is vital should unforecasted adverse weather be encountered, not unheard of on the Alaskan North Slope where the weather can change quickly. Airports and options are few and far between north of the Brooks Range of Alaska. These skills also translate well and are employed for night sling operations, which are still done on a regular basis.

Master your environment

Tuesday, June 9th, 2015

Helicopter pilots work in an amazing, ever-changing environment. The skills necessary to accomplish the task at hand require a high level of concentration, ability, and finesse. Whether it is flying circles around some of God’s greatest work, air medical operations, or instructing the next generation of helicopter pilots how well you utilize your skills can easily be determined by how aware you are with all components of your flying duties. In other words, you must be fully involved and a master of your environment.

WHAT IS YOUR ENVIRONMENT?

You can’t master what you don’t know. Environment can be defined as “the setting or conditions in which a particular activity is carried on.” The activity is easily defined as flying, however, it is the setting or conditions that can make or break you. It would be impossible to list all of the components that define a particular flying environment but several are common to most, if not all, flight operations. These mainstays include: aircraft, airspace, weather, and regulations.

AIRCRAFT If you really want to get to know your aircraft, its systems, and emergency procedures, make a plan to review the Rotorcraft Flight Manual on a regular basis. Pick a chapter in the RFM each month of the year and review it religiously. Know the RFM inside and out.

AIRSPACE I used to wonder why designated pilot examiners and check airmen were so stringent about airspace during checkrides. After a few years of operational flying and getting the life scared out of me by people that didn’t know understand it, I realized why this was a pet-peeve of many examiners. Not knowing airspace is like driving in a foreign country with road signs in a language you can’t begin to comprehend. If it has been a while since you actually used a sectional chart to navigate the various classes of airspace here is a good way to humble yourself; on one of your next flights turn the GPS off. Use good old fashioned pilotage and dead reckoning to find your way. Ask yourself where you are on the chart, where you came from, and where you are going. What airspace are you travelling through? What are the weather minimums? What equipment is required? Transponder? Who do you need to talk to? On what frequency? You get the idea. If you are going to master your environment you must know everything about the airspace you are transiting in and out of.

I have a rule about avionics and eyeballs that are in any aircraft I am flying. No avionics or eyeballs ride for free. If you got’em use them! As an example, if you have two GPS systems use both of them. Use one for your destination and the other for a nearby airport close to your departure area that has an instrument approach in the event you inadvertently fly in to the clouds shortly after take-off.

WEATHER If you think all you need to know about weather comes from those ridiculous questions on the FAA knowledge exams you are mistaken. Most areas experience some sort of regional microclimate. Get to know the weather patterns in your area and when to expect them. If you are flying in an area unfamiliar to you, reach out to other helicopter pilots and pick their brains on local weather patterns. The accident statistics are full of stories about helicopter pilots that didn’t have a working knowledge of local weather patterns.

REGULATIONS In this day and age of technology the current regulations can easily be placed in electronic format on all of your neat gadgets. Know all of the regulations that apply to your particular operations and know them well. If you don’t understand a particular regulation, seek clarification. Wiggle-room has no place when The Man is ready to take enforcement action against you. A quick survey of NASA reports shows several high-time pilots making mistakes involving regulations. Like the Rotorcraft Flight Manual, the federal regulations pertaining to your certificate privileges and operating activities need a periodic review.

HOW TO STAY SHARP? Whatever you do, don’t lose the awe factor. Not long ago I read a story about a 39-year physician. This fellow was in his late 80’s, and he still went to the office every day. His friends and family tried to get him to retire, but he simply refused. He had invented a procedure that he had performed more than 10,000 times. He was asked in an interview if he ever got tired of doing it, if it ever got old. He said, “No. The reason why is because I act like every operation is my very first one.” If you find yourself losing that awe of spooling up and pulling pitch, it may be time for a break. Taking pride in what you do and doing it with excellence can foster an attitude that enables you to master your environment.

OSAPs, HEDAs, and ARAs oh my!

Tuesday, June 2nd, 2015

Imagine being able to create an instrument approach while en-route, and then fly the approach down a minimum of 200 feet and 3/4sm. Not as crazy as it sounds. Here’s why:

IFR helicopters do this regularly, supporting the offshore petroleum industry in the Gulf of Mexico, flying as far as 200 miles offshore to land on ships, drill rigs, spars, and platforms.  All in accordance with Advisory Circular 90-80B: Approval of Offshore Standard Approach Procedures (OSAP), Airborne Radar Approaches (ARA), and Helicopter En Route Descent Areas (HEDA).  The title is certainly a mouthful, and the 58-page document can also be a little daunting. It helps to look at one in action, in this case the popular Copter Delta 30 OSAP, pronounced as “Oh-Sap.”

Before first light, prior to start-up for an IFR flight offshore, which will incorporate an OSAP approach to the destination rig.  Photo by Alex Geacintov

Before first light, prior to start-up for an IFR flight offshore, which will incorporate an OSAP approach to the destination rig. Photo by Alex Geacintov

The Copter Delta 30 OSAP is one of five charted templates in AC90-80B that a pilot can adapt to almost any location offshore. It requires specific two pilot crew training, GPS, ground mapping capable radar, and radio/radar altimeter. It is a SIAP (special instrument approach procedure), and therefore also requires FAA authorization.

While en-route, destination weather is rechecked via radio or satellite phone. If the destination doesn’t have approved weather reporting, normally required under part 135, some operators have an FAA authorization to use remote reporting stations. Operations Specifications are regulatory and issued by the FAA, with some being more restrictive and some less restrictive than the associated FAR. Think of them as an extension of the FARs for specific operators. In this case the Op Spec is less restrictive, which is a good thing because although there are some AWOSs  offshore, there never seem to be enough.

The OSAP Delta 30

The OSAP Delta 30

Wind condition at the destination is used to determine the approach course, which must be into the wind. A DWFAP (down wind final approach point) is typically created 7nm downwind from the destination, on the final approach course. The DWFAP can be created anywhere on the final approach course, as long as it is between 5 and 10nm from the destination. Depending on the en-route direction, a course reversal may be necessary in order to establish the helicopter inbound on course at the DWFAP. All this is planned and created while en-route, and then programmed into the Flight Management System or GPS. Radar in ground-mapping mode is used to determine there are no obstacles within .5nm of the final approach course. The final approach course can be adjusted for obstacles, just as long as it is within 10 degrees of the wind.

When 40nm or less from the destination, a cruise clearance is requested from ATC. This allows an immediate descent to MEA, an eventual descent to 900 MSL 20nm out, and a clearance to fly the approach and missed approach, if necessary.

Once established inbound at the DWFAP, at or below 70 knots (ground speed), a descent from 900MSL to 500MSL can be initiated.

If there are no obstacles within .5nm of course, and the radar and GPS are in agreement within .2nm for the destination target, a further descent from 500MSL to 200RA (radio altitude) can be made.

Radio altitude, from a radio or radar altimeter, is the actual height of the aircraft above the surface, in this case the ocean. The radio altimeter is used to determine the height, while the radar is used to identify obstructions. It’s a dynamic environment and just because an approach was clear of obstacles the day before doesn’t mean a drill ship wasn’t repositioned overnight.

At 1.1nm out, a right or left 30-degree turn is made to avoid overflying the destination, hence the name “Delta 30”. The heading change still has the aircraft converging with the destination, with the MAP (missed approach point) being .6nm away. At the MAP, one can proceed visually to land or go missed approach.

An OSAP is a great procedural tool for the trained two-pilot IFR crew in the offshore environment, providing precision approach-like minimums.

(These views and opinions are my own and do not necessarily reflect the views of Era.)

 

The rig looms ahead after shooting an OSAP Delta 30 instrument approach.  Photo by Paul Patrone

The rig looms ahead after shooting an OSAP Delta 30 instrument approach.  Photo by Paul Petrone

Tips for long cross-country flights

Tuesday, May 26th, 2015

Because I take my helicopter where the work is, I often do long cross-country flights between my permanent and various temporary bases of operation. (After a lot of careful consideration, I’ve decided that it’s safer and more cost-effective to fly the helicopter from point to point than to buy a custom trailer and tow it.) I’ve been making cross-country flights in excess of 500 miles since 2004 and, for six consecutive years, made an annual round trip between the Phoenix area (where I lived) and north central Washington state (where I now live) for cherry drying work. Nowadays, I make an annual round trip between north central Washington and the Sacramento area for frost control. I flew solo on about half of these long flights; the other half was usually spent with a low-time pilot building PIC time at the controls while I tried not to be bored (or sometimes sick from PIO—long story for another time).

I flew home from California in late April. It was another solo flight, one that I’d been looking forward to mostly because I would be doing all the flying. And, instead of the 5-6 hour direct flight, I planned to fly west and then north up the California and Oregon coasts before turning inland again. Total flight time would be about 6-7 hours.

CA Coast

My first look at the California coast on a recent flight from the Sacramento area to Washington State.

Although the flight wasn’t as pleasant and uneventful as I’d hoped, I’m not complaining. But it did remind me of some tips I could share with other pilots preparing to do long cross-country flights.

Planning the Flight

Whether you plan to file a flight plan (which I recommend doing) or not, it’s important to plan for the flight. This pretty much goes without saying. In addition to the usual things to check in advance–weather, fuel availability, TFRs, route options–consider the following:

  • Make your flight segments shorter than they have to be. Sure, Robinson Helicopter claims I can get 16 gallons per hour in my R44 so I should be able to fly 3 hours (less 20 minutes reserve) between stops. But do I really want to fly that long without a break? Probably not–especially after those first two cups of coffee. Yet I’ve seen more than a few flight plans that had us in the air as long as possible.
  • Don’t just study your route before the trip—study everything around it. How many times have I tried to fly up or down the coast, only to be forced inland by a typical “marine layer” of fog? Too many to count. I’ve learned to study my route and alternate routes that would be easy to get to if I needed to change course.
  • Know where the fuel is along the way. Do you think you could make a planned fuel stop if you hit  30 mph headwinds that weren’t in the forecast (or flight plan)? This happened to me on my April flight. I was lucky that there were several airports with fuel along my planned route so I could stop sooner than expected.

Preparing for the Flight

Once you’ve planned the flight, you can prepare the aircraft for conducting the flight.

  • Gather and prepare your charts. If you use paper charts, mark them up with your intended route and fold them with the route easy to access. Then stack them in the order of use. That’s how I used to do it when I used paper. Sure beats fumbling around one-handed. Fortunately, we’re in the 21st century and have tools like Foreflight to provide accurate, up-to-date charts. Make sure you’ve loaded and updated all the charts you’ll need. Use the flight planning tools to mark your route. Then make sure you’re fully charged up and, if necessary, have backup power available. A backup device is handy, too. I use, in order: Foreflight on my iPad, Foreflight on my iPhone, and a panel mounted Garmin 430 GPS.
  • Make an airport and frequency list. I don’t do this much anymore–Foreflight makes it easy to get this info on the fly–but when I used paper charts, I also made a list of all the airports along the way that included frequencies for CTAF (or tower) and AWOS/ASOS (or ATIS). I could then program all the airport codes into my Garmin 430 as a flight plan and make frequency changes as I flew from one airport to the next.
  • Bring oil. I use W100Plus oil in my helicopter. It’s isn’t exactly easy to find. That’s why I usually bring along a quart for every expected fuel stop. That’s not to say that I’ll use it all, but it’s there when I need it.
  • Pack snacks. I always have a small cooler on board for long flights and do my best to fill it with ice (or frozen water bottles) and good snacks before I go. Even if you planned a meal stop along the way, circumstances might prevent you from making that stop. Maybe you had to change your route. Maybe the restaurant closed 30 minutes before you arrived. Or maybe the restaurant that was supposed to be a quarter-mile south is really more than a mile and a half from the only airport gate on the north end of the field. Bringing beverages like water or Gatorade-like drinks is also important. You don’t want to get dehydrated.
  • Pack an overnight bag. If you weren’t planning an overnight stay, pretend you were. A change of clothes, toothbrush, and credit card can make an unscheduled overnight stop a lot more pleasant. And if you think roughing it might be necessary, consider a sleeping bag or bedroll, either of which can make sleeping in an FBO–or the helicopter–a lot more comfortable.
  • Pack an emergency kit. I’ve spent so much time flying over remote areas that I forget that many pilots don’t. My helicopter has an emergency kit under the pilot seat that includes a first aid kit and equipment like fire starters, a signal mirror, a “space blanket,” energy bars, water, and so on. If weight is a factor–and it certainly is in my R44–you’ll have to limit what you bring. But some essentials can save your life if you’re forced to land in the middle of nowhere.
  • Make sure any required power supplies, cables, or batteries are handy. If you rely on electronic devices for navigation, you’d better make sure you’ve got back up power for them. My iPad’s battery can’t survive a 7-hour flight with the screen turned on and the GPS running. I use USB cables hooked up to a power supply to keep the battery charged. If you have a battery-powered GPS, make sure you have a spare set of batteries.
  • Set up your tunes. I listen to music or podcasts when I fly solo. My aircraft’s intercom system automatically cuts the music sound when a radio transmission comes through. Handy.

During the Flight

It’s during the flight that your preparation will really pay off. If you’ve done everything right, you’ll be prepared for anything.

  • Open your flight plan. I recommend filing and opening a flight plan for each segment of the flight. Again, with a tool like Foreflight this is very easy. I can open and close a flight plan with a few taps on my iPad screen. This beats the frustration of trying to reach Flight Service on the radio in a mountainous area when only 700 feet off the ground.
  • Remember that your flight plan is not carved in stone. I can’t tell you how many flight plans prepared by pilots who were accompanying me that went out the window before the second fuel stop. Stuff happens–usually related to weather–and changes are a fact of cross-country flying life. The only time I’ve ever done a long cross-country flight plan exactly as planned was on one trip from Wenatchee, WA (EAT) to Phoenix, AZ (PHX), and that’s because our straight line route across the Nevada desert didn’t have any other options for fuel stops. We had to do it as planned.
  • Know when to pull the plug and wait it out. Weather an issue? While scud running is something we’ve all probably done at one time or another, it probably isn’t something we should be doing. Tired? Tired pilots make mistakes. When low visibility, severe turbulence, or simple pilot fatigue makes flying dangerous, it’s time to set the ship down and take a break. If you did all your homework before the flight, you should know whether there’s an airport nearby to make the wait a little more comfortable. I remember unplanned overnight stays in Rosamond, CA (not recommended) and Mammoth Lakes, CA (which would have been nicer if I’d been prepared for snow).

Experience Is Everything

Low Clouds

Hard to believe that only a few hours after hitting the coast I was forced inland by low clouds and rainy weather.

My April flight was a mixed bag. It started with a beautiful but slightly hazy dawn just west of Sacramento, a gorgeous morning on the coast, moderate turbulence with strong headwinds, low clouds, hazy coastal weather, drizzly rain, more low clouds, even lower clouds (and scud running), and bumpy air on a cloudy day. If you’re interested in details, you can read about it in my blog. Although it isn’t common, it is possible for me to have a perfectly uneventful cross-country flight of 500 miles or more in a day.

If you do enough long cross-country flights, planning and conducting a flight becomes second nature. I’m always thinking about what’s up ahead and working on ways to get more information about alternative routes when things aren’t looking as good as you want them to. I’ve occasionally used my phone to call AWOS and ATIS systems at airports I think might be along a better route. I use radar in Foreflight to get a feel for how weather is moving and where it might be better or worse than I am. I’ll change altitude to avoid mechanical turbulence. If I have to do any scud running, I do it slowly and carefully, always aware of exactly where I am and where I can go if things get worse.

It’s all about planning and preparing and using your experience to handle unexpected situations as they come up. After a while, there’s very little than can surprise you.

Why are we surprised?

Wednesday, May 13th, 2015

After reading a recent accident report I found myself shaking my head in disbelief. Then I got upset and mumbled under my breath “why am I surprised?” In fact, why would anyone be surprised? This blood boiling piece involved the 2013 Alaska Department of Public Safety fatal helicopter accident. It is nearly impossible to recap all of the details of this tragedy in one short article, especially when the NTSB’s final report contained hundreds of pages of facts and circumstances leading to the cause of the accident. However, in general, three lives were lost when an Airbus AS350 crashed near Talkeetna, Alaska, when the helicopter inadvertently flew into instrument conditions during a search and rescue operation.

The NTSB probable cause finding was: “The National Transportation Safety Board determines that the probable cause of this accident was the pilot’s decision to continue flight under visual flight rules into deteriorating weather conditions, which resulted in the pilot’s spatial disorientation and loss of control. Also causal was the Alaska Department of Public Safety’s punitive culture and inadequate safety management, which prevented the organization from identifying and correcting latent deficiencies in risk management and pilot training. Contributing to the accident was the pilot’s exceptionally high motivation to complete search and rescue missions, which increased his risk tolerance and adversely affected his decision-making.”

Few pilots like to second-guess an accident situation, especially when it involves an industry colleague who was fatally injured or killed. But many of the facts regarding the Alaska Trooper accident will make you want to pull your hair out. Several of the facts surrounding this accident are worth highlighting to help prevent such an accident from happening again.

The weather at the time of the initial flight request and during the actual operation was less than ideal. The investigation revealed the pilot was likely blinded by heavy snow fall, low-hanging clouds, and near-zero visibility conditions. According to the NTSB, marginal to worsening conditions were to be expected based on forecasts and current observations. In addition, it was night and the pilot was wearing night vision goggles. Like so many other helicopter accidents we read about he was flying an aircraft not certificated nor equipped for flight in IMC. Although the NTSB’s probable cause made no mention of icing as a contributing factor, icing conditions were ideal at the time of the accident. This is just one of the many factors that would have been obvious with a proper preflight weather analysis.

Should this flight have ever occurred? Absolutely not. Did the operator have weather minimums in place? If you want to call it that. The investigation revealed the Alaska DPS had weather minimums of 500 foot ceiling and 2 miles visibility, which is crazy. What is even more alarming is that the investigation revealed the pilot had set his “own minimums” to include a 200 foot ceiling. This is absolutely ridiculous. Why was a culture like this ever allowed to exist? More on this later.

So, we know the pilot found himself flying in the aforementioned conditions and he lacked the “equipment” but did he possess the necessary skills to survive this type of encounter? No, and here’s why. The accident pilot had not flown a helicopter in IMC conditions since 1986, almost three decades before the crash. Furthermore, it was determined the pilot had no recent or proper training on how to recover from inadvertent IMC encounters.

As previously mentioned, the accident pilot was utilizing NVGs. The investigation revealed the pilot had minimal NVG training. In fact, his only recorded training involving the use of NVGs was in 2003 (10 years prior to the accident) from other pilots within the organization who themselves had questionable NVG training. So, armed with this factual information, why would anyone be surprised by the outcome of this flight?

The NTSB did more than finger-pointing at just the pilot in this case. The culture within the Alaska DPS was also put on trial. Numerous findings were made that detailed agency shortcomings, including a lack of organizational policy to ensure that operational risk is appropriately managed, a lack of mission-specific training, and a lack of adequate information about best practices for helicopter inadvertent instrument meteorological training, just to name a few.

This case could very well be a game changer within the helicopter industry. As a result of the investigation the NTSB made three safety recommendations to the FAA and seven safety recommendations not only to the State of Alaska, but also for 44 additional states, Puerto Rico, and the District of Columbia. This case may very well be the catalyst that will spark many changes much like those witnessed in the HEMS industry in recent years. Unfortunately, sometimes it takes an accident like this to blaze a new trail.

As always, I may be alone but I’m afraid not. So what say you?

Doors-off flying

Wednesday, April 22nd, 2015

Summer is on its way and, in most parts of the northern hemisphere, that means warm weather will soon be upon us. Not every pilot is fortunate enough to fly a helicopter with air conditioning. When I lived and flew in Arizona, it was common for me to take all of the doors off my R44 in May and leave them off until September. It was that hot every single day. (And no, I don’t miss it one bit.)

Of course, pilots don’t need warm weather as a reason to take the doors off. Sometimes the mission you’re flying requires it. Aerial photography is a great example — there aren’t too many photographers who would be willing to pay hundreds of dollars an hour to fly with you and be forced to shoot photos through highly reflective, possibly scratched Plexiglas.

When you remove the doors from a helicopter, you add an element of risk to the flight. Fortunately, the risk can be controlled if you fully understand it and do what’s necessary to reduce or eliminate it. That’s what I want to touch upon in this post.

Loose objects

The most obvious risk is from loose objects blowing around the cockpit or, worse yet, exiting the aircraft. This is a real danger, especially if an object hits the tail rotor or someone/something on the ground.

Want some examples of how dangerous this can be?

  • NTSB WPR14CA363
    “While in cruise flight an unsecured jacket departed the helicopter through an open window. The tail rotor drive shaft sheared as a result of the jacket’s contact with the tail rotors. The pilot subsequently initiated a forced landing to an orchard where during landing, the main rotors struck and separated the tailboom.”
  • NTSB WPR13CA071
    “Prior to the flight, the doors were removed in order to make it easier for the passengers to board and exit the helicopter…. After the two passengers were transported to a work site location, the right rear passenger exited the helicopter and placed the headset on the hook located behind the front seats. After departing the site, about 3 to 5 minutes later while en route at an elevation of about 1,000 feet above ground level, the pilot felt something strike the helicopter. After landing and upon inspecting the helicopter, the pilot discovered that the right rear headset was missing and that the leading edge of the tail rotor had been damaged.”
  • NTSB LAX03TA150
    “While in cruise flight, the back door on the helicopter opened, and a flight jacket that had been unsecured in the back seat departed the helicopter and became entangled in the tail rotor assembly. The tail rotor assembly subsequently separated from the tail boom, and the pilot was unable to maintain control of the helicopter.”
  • NTSB FTW86LA047
    “The pilot failed to assure the cabin door was properly closed before flight, or the cabin door just popped open during flight, allowing an unsecured life vest to blow out the door and into the tail rotor blades. This resulted in the entire tail rotor assembly departing the helicopter.”

(As some of these examples show, you don’t need to have the doors removed to have an unsecured item depart the helicopter and get into the tail rotor.)

Robinson Helicopter warns about this in Safety Notice SN-30, “Loose Objects Can be Fatal.” It recommends that pilots firmly latch all doors and even goes so far to recommend that pilot never fly with a left door removed. (Remember, the tail rotor is on the left side in a Robinson and many other helicopter models.)

I know that my engine starting check list includes an item to assure that loose items are secure. Yours should, too. While this is always important, it’s vital for doors-off flight.

Be sure you warn passengers of the danger of an item exiting the aircraft. Even something as small as a lens cap or lens hood can do significant damage to the tail rotor in flight.

Never Exceed Speed

You might not realize this, but your helicopter’s never exceed speed might be reduced with the doors off. On a Robinson R44, for example, Vne is reduced to 100 knots with the doors off, even if other conditions such as altitude and temperature would allow a faster speed.

My understanding from the Robinson Factory Safety Course is that this reduction of Vne is for structural reasons. (If someone knows better, please correct me in the comments.) There’s more buffeting wind inside the cabin with one or more doors off than with all doors on.

Check the Pilot Operating Handbook for the aircraft you fly the next time you remove doors to make sure you don’t operate beyond doors-off Vne.

Securing Passengers

This might seem like a no-brainer, but if you’re going to remove doors, your passengers had better be secured in their seats with either seat belts or harnesses.

Because some of my aerial photography or video clients like a greater range of movement in their seats than seat belts allow, I have a mountain climbing harness with a suitable strap for securing it to the aircraft frame. I make this available to clients as an option if they don’t have their own. Under no circumstances do I allow my passengers to fly without being secured, especially when their doors are off.

Keep in mind that while a photographer might use a harness to secure himself in the aircraft, you must make sure he knows how to release the harness from the aircraft in the event of an emergency — just as your preflight briefing must tell passengers how to release their seat belts.

 

Dangling Seat Belts

Of course, it was my generous offering of a harness to a photographer that resulted in more than $2,000 of damage to my aircraft when he used the harness but failed to secure the seat belt at his seat. The seat belt buckle dangled outside the aircraft for the duration of our 90-minute video flight chasing racing trucks over desert terrain. On landing, the passenger side fuel tank and area just outside the door frame had at least 50 dings and paint chips in it. How he didn’t hear it repeatedly striking the aircraft near his head is something I’ll never figure out.

Of course, it was my fault for not catching this prior to starting up and taking off. Expensive lesson learned.

Conclusion

While I don’t think there’s anything wrong with taking the doors off a helicopter prior to flight, it does give the pilot more responsibilities to assure that everything is secure and all passengers are properly briefed.

Or isn’t that something we’re already supposed to be doing?

Why wait?

Wednesday, April 15th, 2015

We have a lot of great safety related resources in the industry. If you are flying professionally and have made it to that career goal you set years ago you may be familiar with most of these great resources. However, for reasons I cannot fathom many of these great resources are only introduced after a pilot makes it to his or her career position, whether it is HEMS or another side of the industry. This has to change!

Any HEMS pilot is all too familiar with a risk assessment (RA) tool. In fact, the regulations now require their use. The use of a risk assessment tool is a reminder that every flight has some level of risk associated with it and can sometimes open one’s eyes to previously unforeseen safety culprits. Say what you will, but a properly utilized risk assessment tool can be a tremendous asset when utilized correctly. So, why wait? Why are we waiting until a pilot reaches that first HEMS job at 2,000 or more hours to introduce them to this risk management tool? Why do we have to wait until he hits the 2,000 hour mark to make him safe and professional?

So much time is spent with a new primary flight student on learning to fly that many important facets are being neglected. Any CFI will remember studying the laws of learning and particularly the law of primacy. It states that those things learned first tend to stick with the student throughout his or her flying career. Instead of waiting for 2,000 hours to pass, why not teach the importance of the risk-management process (and tool) from the very beginning? And I do mean from the very first flight; the new student watches the CFI conduct a preflight risk assessment and explains what he or she is doing and more importantly why they are doing it. I have heard of just a couple flight schools utilizing risk assessment tools with students for flight training and I strongly applaud them! Hopefully others will follow suit.

We have other amazing resources for students. The United States Helicopter Safety Team (USHST) does a great job of conducting and providing analysis of helicopter accidents for the purpose of distributing “lessons learned” type of information. This group has produced dozens of nice training bulletins and fact sheets. They should be mandatory reading for any new student. But sadly I am finding that many beginning pilots have no idea what the USHST is. Why wait? CFIs should take the time to introduce the USHST to all of their students. Their website provides mounds of good useful reading material.

Unfortunately air medical related accidents have surfaced on a near regular basis in the United States. Many of the accidents involve inadvertent entry into instrument meteorological conditions. Many in the industry have taken note and developed various mitigation strategies. One of those strategies is an absolutely ingenious concept developed by the National EMS Pilots Association (NEMSPA). This group of highly talented professionals created the Enroute Decision Point (EDP). Simply stated, this concept says that pilots should establish a “trigger-point” when flying in less than perfect weather conditions. Their recent campaign has pushed a “down by 30” concept. This philosophy says that when a pilot finds himself in a deteriorating weather condition that requires him to reduce airspeed by 30 knots it is time to land or turn-around–or go IFR if capable. This is a great concept so, why wait? Why are we as an industry waiting until a pilot reaches the HEMS pilot hour requirements before we teach him this life-saving technique? Inadvertent IMC accidents and are not limited to the HEMS part of the industry.

And finally, Matt Zuccaro and the other fine folks at Helicopter Association International (HAI) have developed the “Land & Live” program. This concept stresses the importance that a pilot should land the helicopter before the situation becomes an emergency, such as in the case of a chip-light, low-fuel, or weather situation. The program has a strong emphasis towards commercial operators to not have a punitive culture for pilots that use good judgment and make the decision to “Land & Live”. This concept may sound like common-sense to many but all too often we read of situations where the outcome could have been entirely different had a pilot used this simple concept. So, why wait? Why not introduce this philosophy very early on in a student’s training?

This article has covered just a sample of the various philosophies and techniques that are being used by the most experienced pilots in our industry. If I haven’t made it clear, we as an industry need to start teaching these and other great safety practices to student pilots very early in their training.

Fly the cloud: Controlling whiteout and brownout

Wednesday, April 8th, 2015

When landing helicopters in potential obscuration conditions, there are two techniques that have worked well for me over the years.  Whether the rotor wash kicks up loose earth causing a brownout or snow causing a whiteout, the techniques used to mitigate the obscuration are alike. While best to avoid these conditions by having ground personnel pack the snow, wet down a dusty area or find another landing zone, there are ways to manage the risk.

Unless you have a wheeled helicopter and a surface for a safe run-on landing, you likely need to land with zero groundspeed. This can be done safely using one of these techniques, without the risk of losing visual references and basically becoming IMC in a hover.

The Shallow Approach

The shallow approach is my preferred method in flatter terrain and a large area without obstructions.

Before discussing the actual approach, the “rotor wash contact point” should be understood. This is the point where the rotor wash meets the ground, and where the obscuration is formed. Its position, relative to the aircraft, is a function of aircraft airspeed, tilt of the rotor disc, and surface winds. All these variables affect where on the ground the obscuration will be formed and where it will drift after being formed. For example, decreasing airspeed or moving the cyclic aft will move the rotor wash contact point closer and more beneath the aircraft. The pilot can control the position of the obscuration cloud, by managing airspeed and the fore/aft position of the rotor disc.

This picture demonstrates the snow cloud being formed perpendicular to the rotor disc. Though this is actually a takeoff and not a landing, the pilot is using proper technique to maintain required visibility and surface references under applicable FAA regulations (FAR 91.155, 91.157, 135.205, and 135.207).

This picture demonstrates the snow cloud being formed perpendicular to the rotor disc. Though this is actually a takeoff and not a landing, the pilot is using proper technique to maintain required visibility and surface references under applicable FAA regulations (FAR 91.155, 91.157, 135.205, and 135.207).

As the approach is made, allow the aircraft to gradually slow down as you near the landing area.  Looking to the side, you will see the obscuration cloud catching up from behind as you slow. Allow the natural drag of the aircraft to be the cause of slowing, not aft cyclic. Any use of aft cyclic will quickly move rotor wash contact point, and thus the obscuration cloud, forward.

With practice it is possible to make a shallow approach to your precise landing spot without aft cyclic, resulting in a touchdown with the obscuration just reaching the mast area. One caveat is that you need to be sure of your touchdown area; this is not the time for a slope landing or to be unsure if it is a suitable landing area. The procedure is to touch down just as the groundspeed reaches zero, without ever having the rotor disc tilt aft of horizontal.

The wind can be beneficial or detrimental, so be sure to make the approach into the wind, even if just a few knots. A headwind will help keep the obscuration aft as long as possible, and help slow down the helicopter to a zero groundspeed without aft cyclic. If the wind is strong you may even be able to hover, keeping the cloud aft. If you need to slow a little quicker during the approach, use a little pedal to get out of trim and increase the drag. If I’m solo I will use the same pedal as the side I’m sitting on, to better see the obscuration cloud behind. If I have another person on board, I will use opposite pedal so that I can better see the landing area, having them watch the cloud.

For training purposes, I have flown over a snowy field at 50 feet and practiced moving the snowy obscuration cloud fore and aft, using the cyclic, but always keeping it behind. With practice you can position it and keep it exactly where you want as you make your approach. Think of it as flying two objects, the helicopter and the cloud.

The Steep Approach

This is a good technique when the area does not allow for a shallow approach, when unsure of the actual landing area, or when there is a hardpan of dirt or snow just below the loose stuff.  This technique does require more aircraft performance than the shallow approach technique, and an extended period of time hovering out of ground effect. Realistically, I do this technique about 80 percent of the time, and the shallow technique about 20 percent.

Make a slow and steep approach to your landing area, keeping the descent rate less than 300 feet per minute; settling with power considerations. Terminate to a hover, typically between 20 and 100 feet, at the first sign of an obscuration forming on the surface. The height this occurs is a good indicator of how bad the obscuration potential is. (I had a rule of thumb flying EMS at night: anything more than 75 feet was unacceptable and I would opt for another LZ.) Hold the hover as the obscuration dissipates. If there is a hardpan under the loose dirt or snow, it will get better. Adjust your altitude as necessary to remain above and clear of the obscuration. In a no-wind condition, it may take a couple of minutes for the obscuration to dissipate.

The fire truck wet down the area prior to the EMS Bell222A landing, helping mitigate the potential for a brownout.

The fire truck wet down the area prior to the EMS Bell222A landing, helping mitigate the potential for a brownout.

If the obscuration dissipates and you think it safe to land, find an object very close to your landing spot to use as a visual reference, preferably just a few feet in front of you at the 2 to 3 o’clock position (sitting right side). A rock, bush, twig will work; anything that won’t blow away. If the rotor wash unexpectedly kicks up more dirt or snow during landing, this may be your only reference to control the helicopter.

Should you ever find yourself in instrument conditions in a hover from a brownout or whiteout, you basically have two not very good options. If still high above the ground, pull max power and hopefully fly out of it without losing control, or if close to the ground lower collective and hopefully land without rolling the helicopter. Be safe and remember:  it’s better to use superior judgment, avoiding the necessity of superior skill.

(These views and opinions are my own and do not necessarily reflect the views of Era.)

CH53s landing in dusty conditions at sunset in Iraq, by pilot Dan Adams.

CH53s landing in dusty conditions at sunset in Iraq, by pilot Dan Adams.

Just say no to traffic patterns

Wednesday, April 1st, 2015

Over the past eight or so years, I’ve done more than my fair share of long cross-country flights with newly minted commercial pilots or CFIs. In most cases, the purpose of the flight was to reposition my helicopter at a temporary base of operations 500 or more miles away and the typically 300-hour pilot on board with me was interested in building R44 time. I was on board as a passenger and got a chance to observe the things these pilots did–or didn’t do. I think the fact that I’ve never been a flight instructor gives me a unique perspective on what I observed.

One thing I’ve come to realize is that typical flight training does very little to prepare students for a commercial flying career. Instead, students are taught to perform maneuvers “by the book,” often so they can teach those maneuvers to their own students in the future. While it’s obviously important to know how to perform maneuvers properly, there are other concerns that are important to commercial pilots. In my upcoming posts for Hover Power, I’ll tackle a few of them, starting with traffic patterns.

I can tell lots of stories about new commercial pilots and CFIs entering traffic patterns to land for fuel at nontowered airports in the middle of nowhere. I can even tell you about the pilot who landed on the numbers of an empty airport’s runway, hover-taxied to the taxiway, and then hover-taxied a half mile down the taxiway to reach the midfield fuel island. They did this because that’s what they had been trained to do. That’s all they knew about landing at airports.

Our flight training teaches us a few things about airport operations, most of which are school-established routines at the handful of airports where we train. There’s a procedure for departing flight school helipads and there may be a procedure for traveling to a practice field nearby. Once there, it’s traffic patterns, over and over. Normal landing and takeoff, steep approach, maximum performance takeoff, run-on landing, quick stop, autorotation–all of these standard maneuvers are taught as part of a traffic pattern. It gets ingrained into our minds that any time we want to land at an airport, we need to enter a traffic pattern.

The reality is very different. Remember, FAR Part 91.129 (f)(2) states, “Avoid the flow of fixed-wing aircraft, if operating a helicopter.” Your flight school may have complied with this requirement by doing a modified traffic pattern at the airport, operating at a lower altitude than the typical airplane traffic pattern altitude of 1,000 feet, or landing on a taxiway rather than a runway. But despite any modifications, it’s still a traffic pattern.

But is a traffic pattern required for landing? No.

Experienced commercial pilots–and their savvier clients–know that traffic patterns waste time. And while the pilot might not be concerned about an extra few minutes to make a landing, the person paying for the flight will be. Why waste time flying around the airport before landing at it? Instead, fly directly to or near your destination and land there.

Before I go on, take a moment to consider why airplanes use traffic patterns. They enter on a 45-degree angle to the pattern to help them see other traffic already in the pattern. They then follow the same course as the other planes so there are no surprises. This is especially important at nontowered airports that don’t have controllers keeping an eye out for traffic conflicts.

But helicopters are avoiding this flow, normally by flying beneath the airplane TPA. As long as they stay away from areas where airplanes might be flying–remember, avoid the flow–they don’t need to worry much about airplane traffic. Instead, they need to look out for other helicopters and obstacles closer to the ground. If a runway crossing is required, special vigilance is needed to make sure an airplane (or helicopter) isn’t using the runway to take off or land. Obviously, communication is important, especially at a busy airport when a runway crossing is involved.

Now you might be thinking that this advice only applies to nontowered airports, where the pilot is free to do what he thinks is best for the flight. But this can also apply to towered airports.

Airport controllers who are accustomed to helicopter traffic and understand helicopter capabilities may instruct you to fly to and land at your destination on the field. You must be prepared to do this, even at an airport you’ve never been to before. That’s part of what your preflight planning is all about. Consult airport diagrams or even satellite images of the airport. Know where you’ll be flying from and where you need to park. Imagine the route to that spot. Be sure to take note of where the tower is–it’s often a great landmark for navigating while close to the ground. Never assume the controller will put you in a traffic pattern. And don’t be afraid to admit you’re unfamiliar if you didn’t do your homework or if things in real life look different from how they looked on paper or a computer screen.

What if a controller does instruct you to enter a traffic pattern and you don’t want to? As amazing as this might seem to new pilots, you can ask the controller to allow you to go direct to your airport destination.

I’ll never forget the flight I had one day as a passenger on my friend Jim’s Hughes 500c. Jim was a retired airline pilot who had been flying helicopters for at least 10 years. We were flying into Prescott Airport (PRC) in Arizona for lunch. When Jim called the tower, he asked for landing at the restaurant. The controller told Jim to enter a traffic pattern that would have required him to fly all the way around the airport, taking him at least 10 minutes out of his way. “Negative,” Jim barked into his microphone. “One-Two-Three-Alpha-Bravo is a helicopter. We want to land direct at the restaurant.” A new pilot at the time, I was shocked by his tone of voice. There was an uncomfortable silence and then the controller came back on and told him he could fly direct to restaurant parking.

 

The airport diagram for Prescott. The X marks the location of the restaurant and we were coming in from the west. Runways 21L and 21R were active. The tower instructed us to fly all the way around the south end of the airport, at least three miles out, to get into a pattern for Runway 21.

The airport diagram for Prescott. The X marks the location of the restaurant and we were coming in from the west. Runways 21L and 21R were active. The tower instructed us to fly all the way around the south end of the airport, at least three miles out, to get into a pattern for Runway 21.

 

Will the tower always grant your request? It depends on the situation. If a runway crossing is involved and the airport is busy with traffic, they might not. It might be safer or more convenient for them to keep you in a pattern with the airplanes. But it can’t hurt to ask, although I don’t think I’d be as aggressive as Jim was that day.

One of the big challenges of becoming a commercial helicopter pilot is thinking like a commercial helicopter pilot. There are things we can do that seem to conflict with what we were taught. Landing at airports without the formality of a traffic pattern is one of them.

Downwind takeoffs and the inherent danger involved

Wednesday, March 25th, 2015

Humans like to push limits. Many have found themselves coasting into the next gas station on fumes, or worse, on the side of the highway. Sadly, this is the same mindset we can fall in to with downwind takeoffs. “I had no problem with a 5 or 6 knot tailwind takeoff last time,” or “I’ve taken off with a 10 knot tailwind. I don’t know why another 5 knots would hurt anything.” You get the point. “Permissible” downwind takeoff limits have often been debated. After all, the only thing two helicopter pilots can agree on is what the third one is doing wrong.

Our self-rationalization can get us in trouble in a hurry. What was a 5 knot tailwind takeoff one day will build progressively until you “accidentally” find out just what that tailwind limit is! I’m not implying that a 3 to 5 knot tailwind takeoff will get you hurt or killed. What I am saying is don’t fall prey to that “I’ll just go a little more this time” mentality that has been known to find its way inside helicopter cabins. It exists and sadly I see it more frequently than I care to admit.

THE MECHANICS

If a picture is worth a thousand words a diagram is worth a thousand explanations (or at least one). Let’s take a look at the mechanics of downwind takeoffs from a technical, yet practical explanation with a basic graphic representation.

Looking at this generic diagram we see three different helicopters each with a certain amount of power being used depending on the airspeed of the helicopter or the relative wind the blades are utilizing. At first sight of the diagram it should remind you of a basic power curve diagram and the fact that our wonderful machines are the only vehicle known to man that take more power to go slower. The power required curve could represent TQ (torque) required for a turbine helicopter or MP (manifold pressure) required. You will see at the bottom of the power required curve we have the “bucket-speed” or the speed at which we get the greatest airspeed for the smallest amount of power required. This “bucket-speed” area should be familiar as it is normally the best autorotative speed range as well. Looking at Helicopter #1 we see a helicopter at or near max power while in a 0-airspeed hover; in or out of ground effect, it makes no difference for this explanation. Granted, it will not always take max power to hover but consider Helicopter #1 at or very near max power for this explanation. Following along with the example helicopters you will see that helicopter #2 now has 15 knots of forward or headwind airspeed and the amount of power required is substantially less than the power required for that 0-airspeed hover. This concept in and of itself is no surprise (or shouldn’t be) to even the most novice students. It is helicopter #3 where we can get into trouble!

Looking at helicopter #3 we see that we have 15 knots of reward or tailwind airspeed. Looking at the power required we see that it is a mirror image of the power required for helicopter #2. It takes the same amount of power, in theory, to hover with a 15 knot tailwind as it does a 15 knot headwind. If you do this bring your tap shoes because you will be dancing on the pedals. (For the sake of aerodynamic argument tail rotor authority and increases in power required with use of the tail rotor are excluded from the equation.) Another way to look at this explanation is that the blades don’t care where the 15 knots of wind is coming from; in essence, with a 15 knot tailwind you could visualize the retreating and advancing blades (as you know them to be) have essentially traded places. I’m certainly not telling you to make a habit of hovering with a tailwind! A host of factors dictate why you shouldn’t, including loss of tail rotor effectiveness issues; yaw stability; longitudinal stability issues due to wind getting under (or over) large stabilizer surfaces; and potential TOT and compressor stall issues in turbine machines.

So, if we have a 15 knot tailwind as seen with helicopter #3 and we commence a downwind takeoff the rotor system is starting with a minus 15 knots of “support,” and therefore must outrun the tailwind and lose the translational lift that it had while stationary. Guess what? That takes more power! Essentially by taking off with this 15 knot tailwind you must use the power necessary to reach the power required area of a 0-airspeed helicopter as we described with helicopter #1. At this point you have a ground speed of 15 knots but the rotor system is experiencing a forward relative airflow of zero; you are getting no help from translational lift, and soon the helicopter will begin to descend. Remember where you are at this point; at or near max power. With the helicopter sinking you add more power, which increases the need for tail rotor robbing you of even more power. This is why I referenced “at or near max power” above. If you were faced with this situation, heavy, and in less than ideal performance conditions you may not have enough power and pedal to get you “over the hump” of the zero airspeed point. This dangerous and often overlooked downwind takeoff condition sets the table for a hazardous cycle.takeoff cycle

While many have fallen prey to pushing the limit with the low fuel light in their car, one must realize that pushing the limit with downwind takeoffs can lead to disastrous results. We must resist the temptation to gradually increase our accepted risk level regarding downwind takeoffs. Obviously with the right power margin and ideal conditions taking off with a certain amount of tailwind speed gradient is possible and can be made safely. It is human nature that we must avoid.

As always, I may be alone, but I doubt it. What say you?