Author Topic: LAA refuse approval to connect Pilotaware to Funke transponder (ADSB out)  (Read 4516 times)


We have completed a permanent installation of Rosetta Pilotaware including connection to our Funke TRT800A Mode S ES transponder with latest firmware (5.3). Carried out by professional avionics engineer who confirmed ground tests and that ADSB working correctly, set to SIL=0 as non certified GPS from Pilotaware. Sent off the relevant mod forms to LAA earlier this year. Just had the following response saying that they (LAA) won't approve the connection for ADSB out because the TRT range does not comply with the ETSO standard. I have seen nothing on this anywhere, with CAA /LAA and everyone else including Pilotaware encouraging installations of EC units and in particular connections to ES capable transponders for ADSB out as a preferred minimum. Advice?

LAA response to modification forms sent in:

Unfortunately, we can’t approve any ADBS-out connection for the Funke TRT series transponders as they do not possess the appropriate approval. The TRT Series is not approved to ETSO Standard C166B, therefore the ADSB out function can not be approved for use until this certification is sought by the manufacturer. The TRT series is sold as “ADSB Ready” but does not necessarily meet the minimum performance requirements of the ETSO. Unfortunately all transmitting avionics installed in LAA aircraft must hold the relevant approval from the CAA, EASA or FAA.
I am sorry this is not the news you wanted to receive. However, you may still use the pilot aware device in your aircraft as standalone electronic conspicuity not connected to that transponder. If you permanently install it you will just need a PMR in your airframe logbook from your inspector.

If this is correct, it throws into serious question why we are being encouraged by all and sundry to spend money on fitting devices which the regulators won't approve. I am struggling to see how this can be right, especially as I have seen nothing on this subject (LAA approval declined) for this elsewhere.


Is Funke aware of this and do they have any comment to make? Just asking...


Have only just got this response from LAA so early days, awaiting comment from our avionics engineer who carried out the fit and provided the mod forms. I am amazed that I have not seen this issue come up anywhere else on the forums, there are some technical issue with Funke transponders mostly relating to firmware updates to make the system work, but I have not seen anyone else say that LAA have declined to approve the connection with PAW.


I don’t think it is specifically connecting to Pilot Aware that is the problem but the snags they’ve had in the past with Funke ES ADSB not having the aircraft’s speed and, as result, showing strange aircraft directions etc, including showing aircraft going backwards. I expect yours, with the new software, works as it should but it would be my guess the LAA are tarring all Funke transponders with the same brush. It might be worth pointing out that your transponder doesn’t do the weird stuff that other Funkes may do.

I’m very pleased I couldn’t get the Funke to fit where I wanted and went for a Trig instead. Pure luck, no judgement  ;D


The product page for that transponder says...

(certification in accordance with ETSO-C166b pending)

So it looks like it's in the works...
Designer and maker of, smart universal USB chargers designed for aviation.  USB power without the RF interference. Approved for EASA installs under CS-STAN too.


I am pretty sure that there are many Funke transponders out there that are emitting DF17 records
So they have been previously allowed, I wonder when the exception came in to play ?


Still waiting on a formal response from Funke on their certification. See the relevant thread on the Flyer Forum which has developed a lot of interest and some movement towards a possible resolution.


The LAA have indicated they are discussing direct with FUNKE.
Europa XS Mode-S ADS-B out enabled.


It will be very interesting to hear the results.

Best Regards



Re: LAA refuse approval to connect Pilotaware to Funke transponder (ADSB out)
« Reply #10 on: January 21, 2021, 09:53:12 am »
Yes good news of positive resolution - LAA Engineering have issued this statement via the Flyer Forum (see that forum post to follow the links mentioned):

As you may know it is possible to connect an uncertified GNSS (GPS) receiver to a range of Mode S transponders in LAA aircraft to provide uncertified ADS-B Out, which we’ve been approving since 2015 following the successful NATS trial.

It was recently brought to our attention that CS-STAN Issue 3 CS-SC005a (issued in 2019) requires that the transponder for such installations must be certified to ETSO-C166b, which covers the approval of a transponder to transmit ADS-B Out. LAA technical leaflet TL3.03 and LAA procedures also require that “transponders installed in UK aircraft must be of a type that has undergone an appropriate approval process by either EASA, the CAA or the FAA”. Given the lack of CAA rules on this subject, LAA interpret this requirement as a transponder providing ADS-B out must also be certified to ETSO-C166b. For the majority of ADS-B installations approved so far, this certification requirement was not of concern as most installations used a Mode S transponder that was certified to ETSO-C166b (ETSO certifications can be checked here).

Upon further research, LAA Engineering understands that a change in the wording to CS-STAN CS-SC005a ‘Configuration 3’ will be made with the next revision of CS-STAN which will remove the requirement for ETSO-C166b certification of the transponder. Please see this EASA FAQ here.

LAA Engineering is therefore satisfied that ADS-B Out installations with a transponder that is not certified to ETSO-C166b is satisfactory for ‘uncertified’ applications. The transponder must still be compliant with an appropriate certification for Mode-S operation, installed in accordance with the manufacturer’s instructions, and the ADS-B Out quality indicators must be set to SIL/SDA = 0.

All previously approved ADS-B Out connections are still valid and any LAA/MOD7 or LAA/MOD14 applications that were previously rejected can now be processed normally.


Re: LAA refuse approval to connect Pilotaware to Funke transponder (ADSB out)
« Reply #11 on: January 21, 2021, 10:06:28 am »

Yes great support from Joe and Steve at the LAA. We have a great team at Turweston.

When you click on the embed link it takes you directly to the pertinent documents..

I would also give a shout out to fellow Europa Club member Mike Pettican from LX Avionics (one of the major vendors the Funke transponder) who has been  extremely active and helpful on this topic over the last few days.


Bob H.


Re: LAA refuse approval to connect Pilotaware to Funke transponder (ADSB out)
« Reply #12 on: January 21, 2021, 10:14:17 am »
Here, here. I wasn't aware of all the work going on in the background, but thanks to all those that put in the effort to achieve this positive and sensible outcome.  :)


After several years of waiting FUNKE are ready to make upgrades to their Transponders. I believe this will meet the required SIL level to be more recognised by other aircraft EC systems, seems the ETSO isn't 'yet' available but I read this and from the info above that it maybe coming.

From the above page:
Important note for ADS-B upgrades: A new firmware / software is available which now makes the ADS-B transmissions of the transponder conform to the RTCA DO-260B standard. Approval of this function according to ETSO-C166b is NOT yet available.
This upgrade is free of charge for devices from S / N 30860816 (delivered from March 2016). For devices from S / N 30580611 to S / N 30860816 (delivered between November 2011 and March 2016), the repair fee applies from MOD11. Devices shipped before November 2011 cannot be upgraded. In this case, we would be happy to offer you a special discount on a new device with simultaneous disposal of the old device.

Fees are €299 or €399 depending on how old your unit is. If it was delivered after March 2016 it maybe free.
I sent mine back recently but due to some confusion it turned out that it wasn't in the serial number band for upgrade (too old), they did however give me a good discount on a new fully compliant one. I had some protracted dealing with them over the years as I was waiting for them to give me the OK for the upgrade and they were very helpful and communications swift. The shipping in and out of the EU was less smooth.
BEFORE SENDING YOUR TXP OFF make sure you check in with them as they will give you info to put on the parcel to smooth it's way through German Customs.
Hope this helps a few of you with the units in the correct serial number band to make yourselves more visible, Regards, Clive


Thanks Clive. Whereas Trig provide updates for free.... Doubt that we will do anything with our Funke at present, not happy about sending them more money for something still not properly certified and their information is unclear as to what this update does. What is the firmware number on yours following the update (ours is 5.3)?