Copter ILS

November 23, 2009 by Tim McAdams

I remember in the mid-1990s Copter ILS approaches began showing up in the New York area. They came from an interpretation by the FAA’s Eastern Region of the Part 97 U.S. terminal instrument procedures (TERPS) that granted helicopters lower minimums. The prevailing thought was that because of a helicopter’s unique maneuvering capabilities the craft could safely operate with lower minimums. I had flown these approaches a couple of times and they seemed to work well.

The Copter ILS approach used the existing ILS, but allowed helicopters a DH of 100 feet and an RVR of not less than 1,200 feet. Although this was basically CAT 2 minimums there was no aircrew qualification required. Moreover, pilots were flying below 200 feet without visual reference to runways that did not have CAT 2 certification. So in 2000, (Copter ILS approaches had been flown for years without incident) citing concerns over technical issues such as signal strength and reliability below 200 feet, threshold clearances and lighting, the FAA issued a Notice to Airmen (NOTAM) that terminated the Copter ILS approaches.

Various industry groups worked with the FAA to help re-establish the lower minimums. Today there are Copter ILS approaches; however, they overlay CAT 2 approaches as this solves the technical TERPS issues. They also require special aircrew and aircraft qualification. An example is Ronald Reagan Washington National Airport (DCA) Copter ILS or LOC RWY 1 approach (www.aopa.org/members/airports/ustprocs.cfm?ID=DCA).

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7 Responses to “Copter ILS”

  1. Ehud Gavron Says:

    It’s interesting that with no reason the FAA NOTAM’d the Copter ILS away. Do you think the crews that were using them were already highly trained specialists (HEMS, SAR, etc.) or was it starting to get used by “hobbyists” and becoming more dangerous?

    E
    (hobbyist … working on instrument rating… enjoying ILS approaches except for having to climb way up just to come down ;)

  2. Avi Weiss Says:

    Hey Tim;

    whatever became of the “Point in Space” approaches that the FAA was working on?

    http://www.faa.gov/about/office_org/headquarters_offices/avs/offices/afs/afs400/afs420/policies_guidance/memorandums/media/Special%20IFR%20Hel%20GPS%20PINs%20Approaches%20atch%202.pdf

    The inception of these started in the mid 90′s, and certainly with access to more accurate GPS signals and WAAS-capable receivers, these types of approaches should now be possible, and enable more pragmatic use of the aircraft for the purpose they were designed for.

  3. Bob Thorson Says:

    The “PINS” approaches in NYC are alive and well. In August 2009 the operational approval period was extended. For a Part 91 operator the use is approved by Letter of Authorization (LOA) from the operator’s FSDO. This guarantees that the operator has the required training, procedures and equipment in place.

  4. Craig Clapper Says:

    I flew many Copter ILS approaches in the S76 to Cat 1 runways in the NY, NJ and CT area and was intimately involved in unsuccessfully trying to save them through the HAI Flight Ops Committee. They were very useful in the overall scheme of things when operating IFR helicopters to the NY City area, especially in the sense of dispatch reliability. With a few Copter ILS in place one could count more on being able to get down to a runway than with just Cat 1 ILS. Their presence led to more flight completions.

    However, what the FAA cited concerning protecting the localizer signals from multipathing at the Cat 1 DA down to the Copter ILS DA of 100′ HAT, the lateral limits allowed pilots on Cat 1 runways using CAT 1 PTS standards (i.e. using 1/2 scale lateral deflection vice 1/4 scale) and possible conflict with aircraft at Cat 1 ILS takeoff hold lines, and Cat 1 approach lighting standards were very real subjects that just could not be overcome.

    Their introduction was well intended albeit not based on anything regulatrory, only the TERPS handbook. Although they were considered successful and very useful, they did not meet the standards set forth for public approaches thus got rescinded. At that time the FAA did not rescind those Copter ILS that were overlaid to Cat II runways.

  5. Bob Dingley Says:

    The lower helo minimums also come into play with selecting alternates. I used to fly the S76 along the Gulf Coast. Many times, after returning onshore after a two hour offshore flight, unforcasted fog rolled in. It is common(helo minimums) to do a Cat 1 ILS with obscured zero, 1/4 mile vis. The heat from the approach lights always burned the fog away and I could always see the lights from miles out. If you are denied the ILS, your options narrow rapidly. And fuel. The S76C+ has 2.8 hrs topped off.

    I otherwise find little difference in a copter ILS and one in a Mooney. Exept the helo has better dual autopilots.

  6. William S. Lyons MD Says:

    In NTSB reports of medical helicopter ambulance accidents in the past 20 or 30 years it is not clear that pilot instrument qualification was either current or approved for helicopters. The crash fatal to 5 persons including the patient, earlier this year at Andrews AFB, at night, in low cloud conditions is illustrative of the problem.

  7. Brendan Fitzpatrick Says:

    Good stuff – thinking about getting my IFR rotorcraft – already IFR fixed wing. Either this or commercial. Keep up the technical stuff.

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