I am having my Cessna 172N avionics upgraded at Solent Airport, due to complete around 5th April. The main features are the installation of a Garmin GTN650 and dual G5s.
The GTN650 requires a post installation flight check, which I feel would overstretch my capabilities at this time. I am a novice PPL with no experience of such ‘advanced’ avionics. To compound matters I have never flown in UK airspace, having obtained my PPL in Mediterranean Europe.
The actual checks (see below) do appear quite straightforward for a more experienced IR pilot familiar with the GTN. I am thinking of procuring the assistance of such a pilot, as passenger or P1, to carry out the checks.
Comments? Suggestions?
Thanks!
Christopher
GPS Flight Check
1. Verify that GPS position is not lost during normal aircraft manoeuvring (e.g. bank angles up to 30 degrees and pitch angles associated with take-off, departures, approaches, landing and missed approaches as applicable).
2. Enter and activate a flight plan on the GTN by pressing the Direct-To button and entering a waypoint. Fly the flight plan and verify that the display of flight plan data is consistent with the CDI indication (deviation, TO/FROM…) in the pilot’s primary field of view.
VHF COM Flight Check
To check the communications transceiver, maintain an appropriate altitude and contact a ground station facility at a range of at least 50 nautical miles. Contact a ground station in close proximity. Press the COM volume knob to select manual squelch and listen for any unusual electrical noise, which would increase the squelch threshold. If possible, verify the communications capability on both the high, low and mid bands of the VHF COM band.
VOR Flight Check
1. Tune a local VOR station within 50 miles.
2. Verify the AUDIO IDENT and VOICE QUALITY have no objectionable electrical interference such as magneto noise.
3. Verify the Morse code decoder IDs the station (95% probability).
4. Fly to and from the station.
5. Verify NAV flag, TO/FROM flag, and CDI are operational.
ILS Flight Check
1. Tune an ILS at the local airport.
2. Verify the AUDIO IDENT and AUDIO QUALITY have no objectionable electrical interference such as magneto noise.
3. Verify the Morse code decoder IDs the station (95% probability).
4. Fly the approach.
5. Verify NAV flag, GS flag, and CDI and VDI are operational.
I am very familiar with the GTN, reasonably local, an IRI and am happy to help.
Just did the same test out of Lee on Solent on Wednesday (for GTN 750/650 installation). Good position – get to Bournemouth for the ILS then when departing on VFR exit to the south once you get near the Isle of Wight you are about 50NM from Shoreham for the VHF check, then to GWC for the VOR. Simples! Plus if you have the terrain alerting check it can be done over the water (hint: check the next page of the STC IM…).
J
@Timothy – That’s brilliant, thanks! I may well contact you nearer the date depending on how things pan out.
@yappmeister – Thanks for the useful information. How long should I allow for the duration of the test flight?
1-2 hours. Depends on how busy Bournemouth are. Call them beforehand and try to arrive 11-3 for their quieter periods. Otherwise it’s how hard you want to work that 172!
Christopher wrote:
Thanks for the useful information. How long should I allow for the duration of the test flight?
I would allow about 45 minutes if Bournemouth or Southampton will have us. Obviously longer if we have to go further (probably Lydd).
Brian knows me well, so if we do find any problems I’ll be able to explain them quickly to him (he knows I know what I am talking about.)
An easy ILS is Lydd EGMD. Phone them with the CC afterwards; £20, IIRC. It is what I normally fly. They prefer you book it with them a few hours beforehand.
I am not suggesting anybody does this 
but if you extrapolate the EGMD ILS backwards, you have quite a long bit in Class G which is nowhere near the published IAP, and this is handy for a quick LOC+GS avionics test, starting at 5400ft.
Very many thanks to @Timothy for his assistance with the test flight last week. Basically I flew where he directed as he tested the avionics functionality. No way could I have done that myself. I also received some welcome IR familiarisation along the way. You’re a scholar and a gentleman Timothy!
For anyone interested here are before and after pictures of the panel:
You’ve gained a lot of functionality without disturbing your panel too much, and it looks like a neat install. Well done!
Did your installer not have the ability to do the flight check? For people doing an upgrade far away from their base, it’s not ideal to discover issues on pick up!
I asked myself the same question right from the start of this thread. Who is the avionic installer that doesn’ t finish his job?
Will you be getting the GFC500 in a second step? The capability vs. that old Century I will be worlds apart…
