GPS approach approvals - a recent change of FAA policy??

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peter-h

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peter-h
I am trying to get my KLN94 approved for approaches.

I am in the UK, flying a US registered aircraft.

The avionics shop doing it has finally tracked down an FAA office willing to talk about it, and got this reply from them:


>>"If this AFMS is for an aircraft which is presently on the AML via an STC
>>and is intended for IFR use than this is no problem. If this AFMS is for
>>the installation of the equipment in an aircraft which is NOT covered under
>>the AML via an STC and is intended to be used for VFR only and is placarded
>>as such and that placard spelled out in the AFMS then again this is no
>>problem. If this equipment is being installed in an aircraft which is NOT
>>covered under the AML via an STC and is being intended to be used for IFR,
>>then that will be a problem and we will not be able to approve this
>>installation unless either an ACO flight test pilot perform a flight test
>>evaluation of the unit installed in the aircraft or a representative
>>delegated by the ACO flight test pilot."
>>
>>
>>
>>It would appear this now allows installation and automatic approval of, for
>>example, a
>>Garmin GNS430W for IFR as the 430W is installed under an STC and AML and
>>Garmin provide an AFMS with the box which is pre-approved by the FAA . The
>>old GNS430 (i.e. non-WAAS) did not have an STC or AML and so would need a
>>flight test by an FAA approved pilot as above to approve the AFMS for which
>>Garmin only provide an un-approved AMFS template which need to be adapted
>>to
>>suit and then signed by the FAA.

Does this make sense to anybody? AC20-138A does not state this. This would create havoc for anybody with a US registered aircraft who has anything other than a Garmin W-series GPS.

If the above is indeed nonsense, can anyone offer the name of an FAA office which is willing to approve a flight manual supplement? The NY IFO should be doing this but seems to be out of the picture.

The aircraft is a Socata TB20GT, made 2002, with the KLN94 installation BRNAV approved by DGAC and the FAA. The US Socata dealers were doing custom FM supplements for their US customers, for years.
 
Well, is the TB20 on the AML for the KLN-94 installation as approved by the FAA or not? Bendix/King tech support should certainly know that.
 
I think it was - the TB20 I flew had a SOCATA AFM supplement for the KLN-94, with an FAA signature on it.
 
I got home and looked at my PIM (information manual that's a copy of a POH) for the TB-20. Supplement 48 covers the KLN-94. interfaced with electromechanical instruments.

If it's helpful, I can scan it to a PDF for you. This isn't assigned to a particular airplane, so no signature on it (or any of the other supplements) but perhaps it may still be useful.
 
Hi Guys,

I have Socata's Supplement 48. This authorises IFR operation enroute but no approaches.

When these aeroplanes were sent to the USA, the local dealers produced the custom supplement required for flying GPS approaches.

Historically, these supplements were easy. You get the template out of the KLN94 Installation Manual (which I have), fill it in, do a flight test as per AC20-138, fill in a 337, send it all to the FAA, and when it comes back you have the customised flight manual supplement....

I have not bothered to do this because, basically, there are so few GPS approaches here in Europe, and all the ones present only duplicate conventional approaches, that they are operationally virtually irrelevant.

Now I am getting around to it. An avionics shop quoted me about $800 (about the going rate here) for producing the custom supplement.

But they got that bizzare reply from the FAA office they contacted. Which is why I posted.

is the TB20 on the AML for the KLN-94 installation as approved by the FAA or not? Bendix/King tech support should certainly know that.
Click to expand...
I will ask re the AML but I don't think Honeywell do/did the AML route like Garmin do.

The KLN94 is on the DGAC and FAA approved Socata TB20 Type Certificate.
 
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Peter,

Honeywell Bendix King did not do an AML. They did an STC for a Mooney M20C. All installations not in a Mooney M20C are done via the field approval process, but you knew that.

I'll call our local FSDO and see how they handle it. I am not aware of any changes in the method that would affect an US registered airplane outside of the country.
 
Peter,

What is the significance of the following notes and limitations in the AFMS?

Note: The KLN 94 is qualified for BRNAV (Basic Area Navigation) operation in the European region in accordance with the criteria of AC
90-96. (Reference ICAO Doc 7030 Regional supplementary Procedures, JAA Technical Guidance Leaflet AUJ20X2 and
Eurocontrol RNAV Standard Doc 003-93 Area Navigation Equipment
Operational Requirements and Functional Requirements (RNAV).)

Note: FAA approval of the KLN 94 does not necessarily constitute approval for use in foreign airspace.​
5. For BRNAV operations in the European region:
(a) With 23 (24 if the altitude input to the KLN 94 is not available) or more satellites projected to be operational for the flight, the aircraft can depart without further action.
(b) With 22 (23 if the altitude input to the KLN 94is not available) or fewer satellites projected to be operational for the flight, the availability of the GPS integrity (RAIM) should be confirmed for the intended flight
(route and time). This should be obtained from a prediction program run outside the aircraft. The prediction program must comply with the criteria of appendix 1 of AC90-96. In the event of a predicted continuous loss of RAIM of more than 5 minutes for any part of the intended flight, the flight should be delayed, cancelled, or rerouted on a track where RAIM​
requirements can be met.

 
John,

Those quotes come from Socata Supplement 48 - or did they come from some locally (USA) done FAA approved supplement?

I don't think they mean anything important. It seems to me that when somebody in Europe approves these things, they always have to invent "something" new to put in there. Europe is a massive job creation scheme.

For example, Supplement 48 states (IIRC) that before any IFR flight the pilot must verify the lat/long of each waypoint and the database must be current.

Typical FAA approach approved supplements (as produced for TB aircraft by US dealers) use the wording out of the KLN94 IM template which says the pilot must verify the lat/long of each waypoint or the database must be current.

This allows flying with an expired database, but with a current database you can just load the flight plan and fly it.

I did some investigation into this and v. or business (because, frankly, verifying the lat/long of every waypoint against the chart is a bit impractical and I could not see why it was thus specified) and Socata's reply was that that was the best they could get out of the DGAC (the French CAA) at the time...

This is the same DGAC which banned the connection of the WX500 stormscope to the slaved compass system, on the grounds that if the stormscope display rotated with the aircraft heading, the pilot could use the stormscope to avoid thunderstorms!!! No kidding; I saw the wording myself. Socata dealers would routinely reconnect the unplugged plug - a 5 minute job - especially in the USA where nobody would accept an aircraft thus crippled. But I found out about this option only from a pilot I found on the internet who happened to buy the very first WX500 equipped TB20 aircraft, which Socata had used for the TB20GT Type Certificate, and he found out about this restriction himself...

It is also the same DGAC which banned the installation of the Shadin (Floscan 201B ) fuel flow transducer IAW the Shadin STC, ahead of the firewall. Instead they required it to be fitted behind the firewall, where the tight bends in the pipe runs caused turbulence which upset the reading by about 25%, but Socata just left it like that, hoping nobody would find out (yeah, right, on a $5000 factory option). US registered aircraft owners were able to re-implement the Shadin STC (Shadin issued the permission freely) but European owners could never do it officially.

:)

I have written to Honeywell...

The KLN94 is quite old now, and I don't suppose many people are installing them new today, but there must be some people still getting them approved for approaches, I would think? The USA is a big place.
 
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Just got this from Honeywell


We don't have an AML for the KLN 94 that covers all of the part 23 aircraft. The AML for the KLN 94 is for the three Cessna models where the TC'd KLN 89B is removed and the KLN 94 is installed in it's place via the STC. We did this for Cessna so they could offer the C-STAR dealers an easy method to replace the TC'D KLN 89B and not have to do individual aircraft approvals.
We do not have an STC for the KLN 94 in any of the TB20 series airplanes. The installer will have to obtain a field approval of the installation in the aircraft using FAA form 337 and our first of type STC in our Mooney. All of the data for the STC is available on the B/K and Honeywell Aerospace tech pubs websites, including the AFMS.
 
peter-h said:
Just got this from Honeywell


We don't have an AML for the KLN 94 that covers all of the part 23 aircraft. The AML for the KLN 94 is for the three Cessna models where the TC'd KLN 89B is removed and the KLN 94 is installed in it's place via the STC. We did this for Cessna so they could offer the C-STAR dealers an easy method to replace the TC'D KLN 89B and not have to do individual aircraft approvals.
We do not have an STC for the KLN 94 in any of the TB20 series airplanes. The installer will have to obtain a field approval of the installation in the aircraft using FAA form 337 and our first of type STC in our Mooney. All of the data for the STC is available on the B/K and Honeywell Aerospace tech pubs websites, including the AFMS.
Click to expand...


This is an N-numbered airplane? Any chance you can work with a stateside shop to do the 337? I don't know if a ferry would be required or if a rep could come over and do the work, then submit it back home. People are buying used 94s today and putting them in airplanes, so I'm certain that if the airplane was in the US you'd be able to get the flight test and the 337 done. I just don't know what wrinkles having the airplane overseas might throw in the process.
 
This is an N-numbered airplane?
Click to expand...

Of course.

Any chance you can work with a stateside shop to do the 337?
Click to expand...

I did wonder about that, as the last resort. I don't see why anybody should care. One could use an avionics shop in the USA - if one was willing. In general terms, AFAIK the shop does not need to see the aircraft.
 
There are several UK mechanics with US A&P/IA ratings. Contact the FAA and they can give you the list of active IA's in the UK.
 
peter-h said:
Of course.



I did wonder about that, as the last resort. I don't see why anybody should care. One could use an avionics shop in the USA - if one was willing. In general terms, AFAIK the shop does not need to see the aircraft.
Click to expand...

I seriously doubt any A&P/IA or radio shop would do anything for an airplane "sight unseen".
 
There are several UK mechanics with US A&P/IA ratings. Contact the FAA and they can give you the list of active IA's in the UK.
Click to expand...

There are many FAA IAs around here (UK). One even works in my hangar.

I did eventually realise that I need only one of these to write out the 337. One catch is that most of them don't know the right procedure for doing this (they rarely work in avionics) and the other is that we are still stuck on which FAA office to send the stuff to. The NY IFO (which covers Europe) apparently doesn't want to do this anymore.
 
peter-h said:
There are many FAA IAs around here (UK). One even works in my hangar.

I did eventually realise that I need only one of these to write out the 337. One catch is that most of them don't know the right procedure for doing this (they rarely work in avionics) and the other is that we are still stuck on which FAA office to send the stuff to. The NY IFO (which covers Europe) apparently doesn't want to do this anymore.
Click to expand...

The FAA in Texas has always been accommodating when it comes to field approvals and such, perhaps your IA there could contact a radio shop in Texas and ask for help.

I would also contact JA Avionics in Chicago and talk with them about this and ask their advise. Sooner or later you'll find the solution but unfortunately it will take a bit of legwork.
 
The latest stage in this project is that the FAA office states that the GPS installation needs to be tested by an "FAA pilot".

Has anybody heard of this requirement????

I have decided to abandon it.

Somebody, somewhere, I think, is pulling somebody's leg, as they say over here.

This GPS installation is on the FAA approved Socata Type Certificate...
 
peter-h said:
The latest stage in this project is that the FAA office states that the GPS installation needs to be tested by an "FAA pilot".

Has anybody heard of this requirement????

I have decided to abandon it.

Somebody, somewhere, I think, is pulling somebody's leg, as they say over here.

This GPS installation is on the FAA approved Socata Type Certificate...
Click to expand...

No, it doesn't need to be tested by a FAA Pilot. You've simply ran into an Inspector that doesn't want to be bothered and wants you to go away.

Your best bet is to find a US Avionics shop and speak with them and find an IA there to coordinate the effort.

And find a different FSDO.
 
peter-h said:
The latest stage in this project is that the FAA office states that the GPS installation needs to be tested by an "FAA pilot".

Has anybody heard of this requirement????

I have decided to abandon it.

Somebody, somewhere, I think, is pulling somebody's leg, as they say over here.

This GPS installation is on the FAA approved Socata Type Certificate...
Click to expand...

I talked to our local FSDO Avionics Inspector. She made several suggestions. She agrees that the Flight Test is performed by the pilot owner or the repair station and she even went to the point to say it really isn't a flight test, but a functional flight evaluation. She suggested getting an explanation from the inspectors manager, and if that was unsatisfactory, to escalate it to the Easter Regional Staff. There is also a quality initiative that takes input from pilots and gets reviewed by FAA staff when wrong, misleading information, or just intransigence from an inspector. If you take a little action escalating the problem, she felt there is a good chance that the inspector will come to his senses. Just because he doesn't do it often enough to understand how it is performed is not an excuse.
 
peter-h said:
John,

Those quotes come from Socata Supplement 48 - or did they come from some locally (USA) done FAA approved supplement?
Click to expand...

The quotes are out of the current installation manual in an appendix with the text of an approved AFMS for the KLN94. You are given instructions on how to edit the text to match your specific installation. You might want to verify the significance of these restrictions.
 
John - thank you for the input; most useful.

Why in particular are you concerned about those statements in the KLN94 IM?

The constellation size is not an issue today. According to Wikipedia, there are 31 today
http://en.wikipedia.org/wiki/Global_Positioning_System

The requirement for an external RAIM predictor is a bit bizzare; I agree.
 
peter-h said:
John - thank you for the input; most useful.

Why in particular are you concerned about those statements in the KLN94 IM?

The constellation size is not an issue today. According to Wikipedia, there are 31 today
http://en.wikipedia.org/wiki/Global_Positioning_System

The requirement for an external RAIM predictor is a bit bizzare; I agree.
Click to expand...

The requirement for RAIM/SBAS checking of enroute and terminal coverage before flight is new, but there's a good website for it at http://www.raimprediction.net/ for US operations. Essentially, since GPS can be used as primary (if you meet all the requirements) nav, you need to ensure that you know of any potential outages before you go, so you can plan for alternative forms of navigation. Garmin G1000 sims have this capability too, and I wouldn't be surprised to see it added to flight planning software in the near future.
 
peter-h said:
John - thank you for the input; most useful.

Why in particular are you concerned about those statements in the KLN94 IM?

The constellation size is not an issue today. According to Wikipedia, there are 31 today
http://en.wikipedia.org/wiki/Global_Positioning_System

The requirement for an external RAIM predictor is a bit bizzare; I agree.
Click to expand...

I am not worried about RAIM or number of satellites, but what does the other note mean. Look it up and verify it doesn't say something that doesn't applly here in the states, such as you must have an FAA inspector perform the flight test, or GPS approaches are not approved, who knows. Ask why it is part of the AFMS, it sure stands out to me? What is Basic Area Navigation, does it include non precision GPS or only enroute and terminal. I repeated the text of the note below for your information.

Note: The KLN 94 is qualified for BRNAV (Basic Area Navigation) operation in the European region in accordance with the criteria of AC 90-96. (Reference ICAO Doc 7030 Regional supplementary Procedures, JAA Technical Guidance Leaflet AUJ20X2 and Eurocontrol RNAV Standard Doc 003-93 Area Navigation Equipment Operational Requirements and Functional Requirements (RNAV).)
 
I have asked the question, John, and will report if/when I hear.

BRNAV is a European enroute thing, mandatory FL095 and above, which is a lateral nav accuracy specification. I don't remember the accuracy level, but it relates to jet INS accuracies and is easily met with GPS.

The BRNAV certification is not only the GPS itself but also the installation, annunciators, etc.

BRNAV can be met with a suitably approved KNS80 (with antenna filters) but practically it can be met only with an IFR GPS.

(Now we are getting PRNAV, which is a tighter accuracy - again easily met by GPS - but with some weird requirements which are being "creatively" interpreted by avionics shops. The KLN94 will never be approvable for PRNAV - Honeywell have confirmed this. There are some PRNAV SIDs/STARs but currently all such airports have alternatives. If PRNAV became an operational (enroute airspace) issue I would replace the KLN94 and one of the KX155A radios with a GNS530W but that would be a major job).

None of this should be a problem because the KLN94 is on the DGAC- and FAA-approved Socata TB20 Type Certificate, which includes BRNAV i.e. the whole thing is IFR enroute approved straight from the factory.

On top of this I have a DGAC letter confirming the aircraft met FAA requirements when manufactured. This highly valuable letter enabled me to transfer from UK reg to FAA (N) reg without having to do an Export CofA.

And finally the many US dealers who sold TB20 aircraft to US customers did not have any trouble getting IFR (approach) approvals. In the USA, this was a non-event.

That's why I don't think that phrase means anything of relevance, but I have asked.
 
Peter,

The note is an affirmative one, but doesn't sound as if it includes GPS approaches. In the EU, what certification is required for GPS approach?
 
In the EU, what certification is required for GPS approach?
Click to expand...

For a European registered aircraft, you get a custom flight manual supplement from EASA.

When GPS approaches first came out, 2-3 years ago, this was a Major Mod (as is any change to a flight manual, over here) and was a big deal (4 digits cost). They must have realised that almost nobody would bother and later made an exemption so that a GPS approach approval supplement was no longer a major mod.

There is also no flight test involved - it is basically a purchase of the papers for a few hundred $.

However, I know of no place in Europe where there is a GPS approach but there isn't a conventional approach with similar (or better) minima. Especially one which has Customs so I can fly there from the UK. This is why I am not spending serious money on this job - it isn't operationally relevant; it is in the "would be nice" category.
 
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