GPS Approach approval

[peter-h]

Hi All,

I am working on getting my KLN94 approved for approaches.

Presently it is approved (Socata TB20GT) for IFR enroute, BRNAV, on the Socata Type Certificate from the DGAC (the French CAA).

There is a process one works through the FAA, based around FAA AC20-138A
http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/0/8a2ae2491c85226f86256e35004c638b/$FILE/AC20-138A.pdf

There is a flight test involved during which some boxes get ticked, a customised Flight Manual Supplement gets produced (a template for this is generally found in the back of the GPS Installation Manual) and then you send off the papers to the FAA.

Now, here is the catch:

Most people work this through an avionics shop. Unfortunately there is not a lot of "meat" on a job like this for the shop and even at US$ 1000 or so (this is the UK) I am now on the 3rd shop and they still haven't done it.

Is is possible for me to prepare the documents myself and send them off to the FAA?

If so, does anybody have a reasonably clear description of the process, including which forms need to go to the FAA and who may sign them? I know several very friendly A&P/IAs so that part would be easy. An FAA Repair Station would be much more difficult.

In my case, I am told that having the BRNAV approval makes it easier but I would prefer to not rely on this.

Many thanks in advance.

Peter

 

[poadeleted20]

I know of no way to do this yourself. AFAIK, this must be done on a 337 signed by an authorized repairman such as an avionics shop with a repair station certificate.

 

[peter-h]

Ron, do you have a reference for that? I've just read the referenced document and cannot see anything in there which says it has to be done by an FAA Repair Station.

On a related topic, does anybody have a flight test schedule applicable to AC20-138A ? The one which the last-1 avionics shop gave me was this one
www.caa.govt.nz/forms/23008.pdf

which is out of date and probably based on AC20-138 (not A).

 

[poadeleted20]

Ron, do you have a reference for that? I've just read the referenced document and cannot see anything in there which says it has to be done by an FAA Repair Station.

Not just a repair station -- any certified repairman or repair station whose ratings authorize this work can do it. The reference would be 14 CFR 43.3 and 43.5.

 

[peter-h]

Would any FAA A&P/IA be enough, I wonder?

 

[John Collins]

Not just a repair station -- any certified repairman or repair station whose ratings authorize this work can do it. The reference would be 14 CFR 43.3 and 43.5.

Ron, there is no requirement that the work be performed by a repair station. An A&P with an IA can sign a 337, if one is required. In most installations today, the installation is considered a minor alteration.

See the excerpt from AC 90-138A below:

(iii) [FONT=AEDNPH+TimesNewRoman,Times New Roman][FONT=AEDNPH+TimesNewRoman,Times New Roman]Minor alteration: Under the original AC 20-138, installation of GPS equipment required the use of approved data (under an STC or major alteration) because GPS was a new and unique technology. However, since GPS technology is now common and considerable experience has been obtained in the installation of GPS, approved data for every installation is no longer appropriate. Instead, installations that do not qualify as major alterations above should be accomplished as minor alterations. These installations should be based on acceptable data including the following:

(A) Data previously approved as applicable to the aircraft (e.g., STC, Approved Model List).

(B) Data previously approved as applicable to a different make/model aircraft (e.g., an initial STC obtained by the equipment manufacturer), provided the installation is installed in accordance with the manufacturer’s instructions, any equipment interfaces are adequately addressed in the installation instructions for the GNSS equipment and the equipment with which it is interfacing, and the equipment is installed in accordance with the guidelines in this AC. For example, installation of GNSS navigation equipment that only interfaces with an antenna, power, ground, an external HSI/CDI with a single source selector switch, and a left/right (deviation-based) autopilot would typically be considered a minor alteration.

[/FONT][/FONT](2) [FONT=AEDNPH+TimesNewRoman,Times New Roman][FONT=AEDNPH+TimesNewRoman,Times New Roman]For these installations, any A/RFM(S) associated with the original approved data should be used as the basis for an A/RFM(S) for this installation. Limitations imposed on the GNSS equipment during the initial approval should be imposed for follow-on equipment approval unless an FAA re-evaluation of the relevant issues determines that they do not apply. An A/RFM(S) is not necessary if it was not part of the original installation, if the operating manual addresses the use of the equipment and Page 12 Par 8 12/22/03 AC 20-138A associated installed components (e.g., remote source selection), and there are no unique limitations associated with the particular installation.

[/FONT][/FONT](3) [FONT=AEDNPH+TimesNewRoman,Times New Roman][FONT=AEDNPH+TimesNewRoman,Times New Roman]The installation performance tests (paragraphs 22 and 23) must be successfully completed. The installation performance tests are usually conducted in two parts, the ground checks and the flight checks. The aircraft can be approved for return to service following the required ground checks, however the GNSS equipment cannot be used for flight under Instrument Flight Rules (IFR) until the flight checks have been accomplished and would have to be placarded as such.
[/FONT][/FONT]

 

[poadeleted20]

Would any FAA A&P/IA be enough, I wonder?

I should think so, provided the individual is qualified for the particular task. See 14 CFR 65.81:

However, he may not supervise the maintenance, preventive maintenance, or alteration of, or approve and return to service, any aircraft or appliance, or part thereof, for which he is rated unless he has satisfactorily performed the work concerned at an earlier date. If he has not so performed that work at an earlier date, he may show his ability to do it by performing it to the satisfaction of the Administrator or under the direct supervision of a certificated and appropriately rated mechanic, or a certificated repairman, who has had previous experience in the specific operation concerned.

I don't know how many A&P's out there are thus qualified for IFR GPS installation and certification. OTOH, just about every certified avionics shop is.

 

[poadeleted20]

Ron, there is no requirement that the work be performed by a repair station.

I believe that's what I said above -- a certified repairman or repair station with the appropriate ratings. That includes...

An A&P with an IA

...for a major alteration.

In most installations today, the installation is considered a minor alteration.

...which still requires a repairman (mechanic) with an airframe rating. The point is that this isn't something a pilot can do himself without a repairman certificate/rating.

 

[peter-h]

Thank you guys. As I posted earlier, I can get an A&P/IA easily, but anything beyond that restricts the options very much.

On a related topic, does anyone have any views on what the situation is if the aircraft is already BRNAV approved (in this case this means IFR enroute, not terminal operations or GPS approaches) on its original Type Certificate? I have been advised that this makes it easier to get the Approach approval (i.e. the full FAA IFR approval which is not limited in any way) because it eliminates the ground test portion of AC20-138A.

I found a DGAC (the French CAA; the issuer of the original TC which was also accepted by the FAA) document
https://www.sia.aviation-civile.gouv.fr/dossier/texteregle/BRNAV_ANN04_V1.pdf
which says that compliance with AC20-138 is enough (it is dated before 138A came out).

So, since AC20-138 compliance was required for the BRNAV approval, and since the FAA recognised the TC, and since the FAA also accepts the Flight Manual GPS supplement authorising IFR enroute, what exactly does this save me in terms of time/effort (if anything).... ??

About 3 years ago, an avionics shop which was looking into the Approach approval for me (but never did anything) reported that they phoned the UK office of the FAA (located at London Heathrow Airport) who verbally confirmed that if my GPS supplement has the rubber stamp of the TC issuer (the DGAC in this case), which mine has, then the FAA will accept that as is. An FAA DAR confirmed a year or two later that this is correct. This means my present installation is good for IFR enroute even though I don't have the tail number specific GPS supplement which is customary in FAA-land. The question now is what, if anything, this means for the Approach approval, since this DGAC approval must have complied with AC20-138 in the first place... Since AC20-138 is pretty similar to 20-138A, my reading of this situation is that I don't actually need to do anything! I could just get the 337 written up, quoting the DGAC BRNAV approval, and send it in.

 

[John Collins]

I believe that's what I said above -- a certified repairman or repair station with the appropriate ratings. That includes...

...for a major alteration.
...which still requires a repairman (mechanic) with an airframe rating. The point is that this isn't something a pilot can do himself without a repairman certificate/rating.

Ron,

I am only hung up on your implication that a mechanic is a subset or a category of a repairman.

A mechanic with an Airframe mechanic certificate is not a subset of a repairman. A repairman may be an A&P mechanic, but it is not one of the requirements. I know of at least three categories of a repairman certificate, a repairman who works for a repair station and can only exercise his certificate in the employment for the repair station, a repairman of an experimental home built aircraft that was the primary builder of the aircraft, and a relatively new category of repairman for LSA aircraft. So when you say " a certified repairman or repair station with the appropriate ratings", you leave out an A&P mechanic, or at least a mechanic with an airframe rating.

I agree that the pilot can't do this minor modification without an A&P or a repairman working for a repair station providing supervision and making the log book entry.

As a practical matter, if the GPS is already approved for VFR and meets the requirements for IFR, there are only a few paperwork tasks, a ground test, and a flight test to be performed, in some cases an AFMS needs to be prepared, a placard affixed to the panel and a logbook entry to be made. In my experience, pilots are mostly the ones who conduct the flight test, sometimes all they are given is a check list to follow and record the flight test results for the mechanic.

 

[John Collins]

Thank you guys. As I posted earlier, I can get an A&P/IA easily, but anything beyond that restricts the options very much.

On a related topic, does anyone have any views on what the situation is if the aircraft is already BRNAV approved (in this case this means IFR enroute, not terminal operations or GPS approaches) on its original Type Certificate? I have been advised that this makes it easier to get the Approach approval (i.e. the full FAA IFR approval which is not limited in any way) because it eliminates the ground test portion of AC20-138A.

I found a DGAC (the French CAA; the issuer of the original TC which was also accepted by the FAA) document
https://www.sia.aviation-civile.gouv.fr/dossier/texteregle/BRNAV_ANN04_V1.pdf
which says that compliance with AC20-138 is enough (it is dated before 138A came out).

So, since AC20-138 compliance was required for the BRNAV approval, and since the FAA recognised the TC, and since the FAA also accepts the Flight Manual GPS supplement authorising IFR enroute, what exactly does this save me in terms of time/effort (if anything).... ??

About 3 years ago, an avionics shop which was looking into the Approach approval for me (but never did anything) reported that they phoned the UK office of the FAA (located at London Heathrow Airport) who verbally confirmed that if my GPS supplement has the rubber stamp of the TC issuer (the DGAC in this case), which mine has, then the FAA will accept that as is. An FAA DAR confirmed a year or two later that this is correct. This means my present installation is good for IFR enroute even though I don't have the tail number specific GPS supplement which is customary in FAA-land. The question now is what, if anything, this means for the Approach approval, since this DGAC approval must have complied with AC20-138 in the first place... Since AC20-138 is pretty similar to 20-138A, my reading of this situation is that I don't actually need to do anything! I could just get the 337 written up, quoting the DGAC BRNAV approval, and send it in.

Peter,

You should not need a 337, just a logbook entry. You need to follow 138A which requires a ground and a flight test and you should remove the placard “GPS APPROVED FOR VFR ONLY” and install a placard “GPS NOT APPROVED FOR IFR PRECISION APPROACH”.

 

[RotorAndWing]

Peter,

You should not need a 337, just a logbook entry. You need to follow 138A which requires a ground and a flight test and you should remove the placard “GPS APPROVED FOR VFR ONLY” and install a placard “GPS NOT APPROVED FOR IFR PRECISION APPROACH”.

The requirement of the 337 will vary from FSDO to FSDO. One will require it, the other will not.

The good news is all 337's are now submitted directly to OKC, scanned and entered into record therefor bypassing the local FSDO. So it's really up to the comfort level of the IA returning to service.

 

[peter-h]

John -

You should not need a 337, just a logbook entry. You need to follow 138A which requires a ground and a flight test and you should remove the placard “GPS APPROVED FOR VFR ONLY” and install a placard “GPS NOT APPROVED FOR IFR PRECISION APPROACH”.

Which approval are you describing; the one for approaches or the one for enroute IFR?

My current (ex factory) placard says "approved for IFR enroute, not sids/stars or approaches".

My "feeling" is that since the current approval must have met AC20-138 (this is a ~ 2000 Type Certificate, so predating AC20-138A) I should meet the ground and flight test requirements for approaches too, already.

The one issue is that I still need a Flight Manual supplement authorising this, and a FMS needs a 337, doesn't it?