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Tag: helicopter (page 2 of 2)

Goodbye Sikorsky S300

The focus at last week’s Heli-Expo in Orlando was naturally on the larger end of the helicopter market, from the first public display of the AgustaWestland AW609 Tiltrotor to Airbus Helicopters’ snazzy unveil of the H160. But one of the more interesting moments came almost as a footnote at a poorly attended Sikorsky press conference.

“Everyone’s always interested in the lights,” said Dan Hunter, director of Sikorsky’s commercial line. Yet despite that interest, Sikorsky has all but killed the S300 and its derivatives. Hunter said the company won’t take any new orders, focusing instead of filling its very slim backlog that has come from foreign government sales as part of group buys. Hunter said Sikorsky is working hard to firm up the supply chain in order to produce these few orders, and to a certain extent, to fill parts requests.

And therein lies the good news for current S300 operators. What was a dire situation a year or two ago with parts availability and factory support now seems to be something less than an emergency situation. “We’re not there yet, but we’re working to get it done,” Hunter said. The same inventory and support goals for the company’s other products also extend to the S300 and its variants.

On some level, I don’t blame Sikorsky. The aftermarket support brings in about $10 million a year, Hunter said. For sake of comparison, that’s about the cost of a new S-76D. When the bosses are sitting in a board room trying to figure out where to allocate resources it’s hard to justify the expense of establishing an inventory and support staff for a business that brings in the same revenue as one additional airframe sale. Why give a business unit leader a few million bucks and tell her to spend all her time contracting and supporting a supply chain when you can give Jim an expense account and tell him to sell one more helicopter?

Which does open the question of why Sikorsky bought the type certificate in the first place. To that, Hunter says he is convinced that knowing what they knew at the time it was a good buy. Peel back the layers, he says, and problems started to emerge. The manufacturing process wasn’t up to Sikorsky standards, he said. No offense, Elmira.

So, does that mean the S300 and its cousins are destined for a long life of purgatory, existing only on a piece of paper? Maybe not. Hunter hinted many times that Sikorsky could offload the business at the right time. It might work under someone else, he said.

The multiengine height-velocity diagram

The last two blogs provided great explanations of the height-velocity diagram as it pertains to single engine helicopters. So, let’s now take it a little further into the multiengine helicopter realm.

Just as with singles, you will typically find a H-V diagram for multiengine helicopters in the flight manual. However, unlike the singles, the H-V diagram for the multi is to insure a safe landing OEI (one engine inoperative), and not from an autorotation. Furthermore, whether or not the H-V diagram even applies is dependent on how well the aircraft can perform OEI. This performance is defined in a series of categories. If the multi is full-time Category B (as are all singles), or a part-time Cat B, then a H-V diagram limitation will apply; whereas, if Category A it will not. Basically, Cat A is where OEI performance is so good that the H-V is not applicable. Comparing three very different multiengine helicopters to highlights these differences.

The BO105CBS is full-time Cat B, with marginal OEI performance. Even in ideal conditions (light weight and low density altitude), it can barely hold altitude on one engine. Varying airspeed from Vy just a couple knots results in a descent. Approach and departure profiles AEO (all engines operating) need to be such that a quick transition can be made in accordance with the H-V diagram, in the event of an engine failure.

The Bell 412 is an example of a multi that can be operated Cat A or Cat B, depending on the weight, altitude, and temperature. At lower weights, altitudes, and temperatures it will have good enough OEI performance to qualify as a Cat A aircraft. However, in most day-to-day operations it is typically a Cat B aircraft, which means the H-V diagram would apply.

 

multi hv

Bell 412 H-V diagram

 

The AgustaWestland 139 is a true Cat A aircraft, although as with many other Cat A aircraft it is possible to find conditions that will push it into Cat B. The AW139 was largely designed to operate Cat A, in an offshore petroleum support environment with a high useful load (passengers, cargo, and fuel). It is capable of landing and taking off from helipads, while carrying up to 15 passengers, with Cat A performance.

 

AW139 height-velocity chart

AW139 H-V diagram

 

So, what is Cat A?  Cat A is where the aircraft has adequate performance capability for continued safe flight in the event of an engine failure, no matter when that failure occurs. While single engine and Cat B multiengine helicopters have no such assurances, the Cat A aircraft is able to ensure that a safe and normal landing can be made OEI at an airport or heliport.

In the event of an engine failure, different types or categories of helicopters dictate different courses of action in order to do the same thing: preserve rotor RPM. No matter the helicopter and its’ number of engines, Nr is the wing and it must be maintained. The single must obviously enter an autorotation. The Cat B multi must fly at or above Vy (best rate of climb OEI) in order to maintain or increase altitude, and then fly to an area where a safe landing can be made. During takeoff and landing while close to the ground and below Vy, an engine failure in a Cat B will likely result in a forced landing. Though not as dire as an autorotation, it is more of an event than the Cat A helicopter. The difference with the Cat A is that engine failure doesn’t dictate a forced landing. In the event of an engine failure during takeoff, a Cat A has the ability to either return to and safely stop at the takeoff area or to continue takeoff, climb and establish forward flight. In the event of an engine failure during landing, the Cat A can either land at the intended landing area or abort the approach and reestablish forward flight. Unlike Cat B, there is no exposure to the possibility of a forced landing, hence no H-V diagram.

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

Markus Lavenson is currently flying for Era Helicopters as a captain in the Sikorsky S92 and Leonardo Helicopters AW139 in Alaska and the Gulf of Mexico in oil and gas support missions. His varied career began shortly after graduating from the University of California at Davis, and has included everything from flight instruction and powerline patrol to HEMS and external load operations. His more than 10,000 hours of flight time comes from more than a dozen different types of helicopters and airplanes. Holding an ATP helicopter and commercial multi-engine fixed-wing, he also is a flight instructor fixed-wing and instrument flight instructor helicopters. Lavenson enjoys the intricate work of helicopter instrument flying, whether it’s to an airport on Alaska’s North Slope or one he creates to an oil rig hundreds of miles offshore.

Maximum performance takeoffs and judgement calls

Ed note: In the last post we covered the mechanics of the Height-Velocity Diagram. Here author Maria Langer discusses an application of its use. 

This past summer, I was part of a helicopter rides gig at an airport event. There were three of us in Robinson R44 helicopters, working out of the same rather small landing zone, surrounded on three sides by parked planes and spectators. We timed our rides so that only one of us was on the ground at a time, sharing a 3-person ground crew consisting of a money person and two loaders. Yes, we did hot loading. (Techniques for doing that safely is fodder for an entirely different blog post.) The landing zone was secure so we didn’t need to worry about people wandering into our flight path or behind an idling helicopter.

The landing zone opened out into the airport taxiway, so there was a perfect departure path for textbook takeoffs: 5-10 feet off the ground to 45 knots, pitch to 60, and climb out. It was an almost ideal setup for rides and we did quite a few.

One of the pilots, however, was consulting a different page of the textbook: the one for maximum performance takeoffs. Rather than turning back to the taxiway and departing over it, he pulled pitch right over the landing zone, climbed straight up, and then took off toward the taxiway, over parked planes and some spectators. Each time he did it, he climbed straight up a little higher before moving out.

I was on my way in each time he departed and I witnessed him do this at least four times before I told him to stop. (I was the point of contact for the gig so I was in charge.) His immediate response on the radio was a simple “Okay.” But then he came back and asked why he couldn’t do a maximum performance takeoff.

It boggled my mind that he didn’t understand why what he was doing was not a good idea. The radio was busy and I kept it brief: “Because there’s no reason to.”

The Purpose

The Advanced Flight Maneuvers chapter of the FAA’s Helicopter Flying Handbook (FAA-H-8083-21A; download for free from the FAA) describes a maximum performance takeoff as follows:

A maximum performance takeoff is used to climb at a steep angle to clear barriers in the flightpath. It can be used when taking off from small areas surrounded by high obstacles. Allow for a vertical takeoff, although not preferred, if obstruction clearance could be in doubt. Before attempting a maximum performance takeoff, know thoroughly the capabilities and limitations of the equipment. Also consider the wind velocity, temperature, density altitude, gross weight, center of gravity (CG) location, and other factors affecting pilot technique and the performance of the helicopter.

This type of takeoff has a specific purpose: to clear barriers in the flight path. A pilot might use it when departing from a confined landing zone or if tailwind and load conditions make a departure away from obstacles unsafe.

The Risks

This is an “advanced” maneuver not only because it requires more skill than a normal takeoff but because it has additional risks. The Helicopter Flying Handbook goes on to say:

In light or no wind conditions, it might be necessary to operate in the crosshatched or shaded areas of the height/velocity diagram during the beginning of this maneuver. Therefore, be aware of the calculated risk when operating in these areas. An engine failure at a low altitude and airspeed could place the helicopter in a dangerous position, requiring a high degree of skill in making a safe autorotative landing.

And this is what my problem was. The pilot had purposely and unnecessarily decided to operate in the shaded area of the height velocity diagram with passengers on board over an airport ramp area filled with other aircraft and spectators.

Height Velocity diagram for a Robinson R44 Raven II. Flying straight up puts you right in the “Deadman’s Curve.”

Height Velocity diagram for a Robinson R44 Raven II. Flying straight up puts you right in the “Deadman’s Curve.”

Seeing what he was doing automatically put my brain into “what if” mode. If the engine failed when the helicopter was 50-75 feet off the ground with virtually no forward airspeed, that helicopter would come straight down, likely killing everyone on board. As moving parts came loose, they’d go flying through the air, striking aircraft and people. There were easily over 1,000 people, including many children, at the event. My imagination painted a very ugly picture of the aftermath.

What were the chances of such a thing happening? Admittedly very low. Engine failures in Robinson helicopters are rare.

But the risks inherent in this type of takeoff outweigh the risks associated with a normal takeoff that keeps the helicopter outside the shaded area of the height velocity diagram. Why take the risk?

Just Because You Can Do Something Doesn’t Mean You Should

This all comes back to one of the most important things we need to consider when flying: judgment.

I know why the pilot was doing the maximum performance takeoffs: he was putting on a show for the spectators. Everyone thinks helicopters are cool and everyone wants to see helicopters do something that airplanes can’t. Flying straight up is a good example. This pilot had decided to give the spectators a show.

While there’s nothing wrong with an experienced pilot showing off the capabilities of a helicopter, should that be done with passengers on board? In a crowded area? While performing a maneuver that puts the helicopter in a flight regime we’re taught to avoid?

A responsible pilot would say no.

A September 1999 article in AOPA’s Flight Training magazine by Robert N. Rossier discusses “Hazardous Attitudes.” In it, he describes the macho attitude. He says:

At the extreme end of the spectrum, people with a hazardous macho attitude will feel a need to continually prove that they are better pilots than others and will take foolish chances to demonstrate their superior ability.

Could this pilot’s desire to show off in front of spectators be a symptom of a macho attitude? Could it have affected his judgment? I think it is and it did.

Helicopters can perform a wide range of maneuvers that are simply impossible for other aircraft. As helicopter pilots, we’re often tempted to show off to others. But a responsible pilot knows how to ignore temptation and use good judgment when he flies. That’s the best way to stay safe.

Photo of the Day: News ‘copter

 

 Mike Fizer photographed the Eurcopter Astar, a news helicopter for a Fox Channel 5 affiliate in New York City, near the Empire State Building.—Jill W. Tallman

This month in solos: July 2012

The 24-hour news cycle is a blessing and a curse for general aviation. A curse, because now anybody who has ever had a gear-up, an emergency landing, or even a “hard landing” is likely to find themselves the subject of breathless-bordering-on-sensational coverage. A blessing, because the happy events of general aviation–like solos and certificates–are now finding their way into the mainstream media more often. From time to time we’ll post the good stories so that we, too, can celebrate the successes. Congratulations to all!

  • Ashley Peniston of Chillicothe, Missouri, soloed a Cessna 172 on July 17. According to the Chillicothe News, Ashley was the first female to solo at Chillicothe Municipal Airport since 2000. (!) She did get her shirt-tail cut (there’s a great photo with her instructor, Mike Langwell). Note to the Constitution-Tribune: It’s yoke, not “yolk.” Ashley and her husband, Bob, are both pilots. Bob soloed on Feb. 25.
  • CAP Cadets Matthew Angelo and Jack Nordell soloed in July. Both are from Canon City, N.M. According to the Pueblo Chieftain, Angelo flew at Fort Pickett, Va., and Nordell flew at Shawnee, Okla. A photo shows the cadets in CAP uniform, holding their cut shirt tails.
  • Robert Pinksten of Nashua, N.H., soloed a helicopter on July 2. The Nashua Telegraph was quick to crown Robert “Youngest in New England to Pilot Helicopter Solo,” but we’re also happy to give Robert his props, since you don’t see teens soloing helicopters every day. We also love it when media solemnly inform readers that the soloing youngster will be flying an aircraft before he is driving a car. —Jill W. Tallman

How we get the shots: May 2012 cover

Call us wimps, but your Flight Training editors weren’t willing to put a perfectly good airplane down in a field so as to provide that extra level of realism needed to illustrate “You Were Ready for This,” which appears on p. 24 of the May 2012 issue.

But we–that is, I was willing to allow my 1964 Piper Cherokee to be towed into the grass beside Taxiway H at Frederick Municipal Airport. Then, photographer Chris Rose took to the skies in a helicopter (supplied by Advanced Helicopter Concepts) to get shots of my airplane from overhead.

Chris Anderberg, who works in our accounting and finance department, portrayed a pilot who has successfully executed an off-airport landing and is checking out the possible “damages.” (We often grab unsuspecting colleagues out of their cubicles and offices to play bemused, scared, excited, or frustrated pilots. They usually deliver the goods.)

With base shots in place, Rose used Photoshop to remove the surrounding airport environment (which includes a row of hangars, runways, taxiways, and a brand-new air traffic control tower) and put in some furrows.

Now that you know, how do you think he did? –Jill W. Tallman

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