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IO540
9th Sep 2010, 13:27
One cannot fly GPS/RNAV approaches unless the Flight Manual Supplement for the GPS authorises this.

Enroute IFR, or BRNAV only, etc, is not enough. It has to authorise either unconditional "IFR" or "enroute, terminal and approaches" explicitly.

The above is true for both FAA and EASA aircraft.

If the Flight Manual Supplement authorises BRNAV only, is it legal to fly the approach in VMC?

Context: UK Class G airport.

It seems obvious to me that it is legal to fly the approach outside the airport's ATZ but that's not very useful...

Fuji Abound
9th Sep 2010, 20:34
Hasnt this been done before (maybe on the darker side)? I seem to recall the conclusion was that if you request the adminstering "authority" (viz ATC) to fly an approach visually and they agree then you are entitled to do so without compliance with either the pilot being qualified to operate in IMC or the aircraft having the required equipment. This would seem to make sense since you are simply conducting an alternative visual approach.

Mind you I am not sure what this achieves other than proving "you" and the aircraft can perform a GPS aprroach. Where in Europe is there a useful GPS approach where there is not an equally acceptable alternative that you would be able to fly? I havent checked recently but doesnt Shoreham, Exter, Durham, Staverton and Blackpool (not sure about Blackpool) all have alternative as does Lillle which is the closest European GPS approach that comes to mind. I appreciate the alternatives at Shoreham are usually broken mind you but in theory they should be operationally.

IO540
9th Sep 2010, 21:14
Yes, clearly nothing stops you flying a long final which just happens to track say the ILS... but then ATC is entitled to give you an orbit at 2 miles to let some instrument traffic in :)

If OTOH you ask for a "visual approach" (which is an IFR procedure) then ATC will expect you to fly a tight visual approach, not the full T-shaped GPS monty.

Where in Europe is there a useful GPS approach where there is not an equally acceptable alternative that you would be able to fly? I havent checked recently but doesnt Shoreham, Exter, Durham, Staverton and Blackpool (not sure about Blackpool) all have alternative as does Lillle which is the closest European GPS approach that comes to mind. I appreciate the alternatives at Shoreham are usually broken mind you but in theory they should be operationally.

Well, quite. You can fly the navaid-based approach using the existing GPS, without the GPS being approved for GPS approaches. It is only when flying a GPS approach with a GPS that the GPS needs to be approved for approaches. Totally perverse.

UK's requirement for mandatory ATC for any approach, and the fact that under the privatised ATC system the airfield will be billed for the radar service if there is no ATC providing a procedural separation, which it cannot (in most candidate cases) afford to pay, means that GPS approaches are likely to remain of marginal relevance in the UK. They might just become popular at places like Shoreham which already have ATC but can't afford to repair the broken DME.