A must read for all IFR pilots. How you can get into a pickle by not fully understanding your systems and not cross checking.
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The lesson appears to be that if you fly an NDB approach using the GPS, you still have to use the real DME for distances. The GPS is good for lateral nav only.
As long as we have those unnecessarily complicated and old-school non-precision approaches with directional guidance from one navaid and distance information from another, these accidents will continue to happen occasionally. Shouldn’t happen (approach briefing and nav setup!), but they do happen.
Even on a simple (LNAV) GPS approach, this wouldn’t have happened, as these use the same source for both course and distance information. No DME involved.
An LPV (or an ILS) is even safer, as the glideslope safeguards against starting the descent too far out.
That’s another reason while i will always rather fly an LPV or even LNAV/VNAV …
The report is intersting, but when i read stuff like “outbound radial from the NDB” i start to shiver. If the professionals can’t get the terminology right … and the whole report is full of confusing stuff like that.
Peter wrote:
The lesson appears to be that if you fly an NDB approach using the GPS, you still have to use the real DME for distances. The GPS is good for lateral nav only.
The lesson is rather than if you use GPS as a substitute for a DME, you should make very sure that the GPS waypoint is at the DME location.
They would have been alive if they flew the NDB ILS and switched the GPS off. It’s all about cross checking various sources.
That’s what Bosco said – but eventually you WILL make a mistake here, it’s more a matter of when than “if”. The mixing of nav sources is a real danger today. Had he simply flown the right altitude and waited for the the Loc and GS he would have been fine …
That’s another reason while i will always rather fly an LPV or even LNAV/VNAV …
That would be tricky
Had he simply flown the right altitude and waited for the the Loc and GS he would have been fine …
Obviously, he wasn’t flying the ILS.
I was speaking in general, that i will prefer an LPV over an ILS any time.
Sorr, i misunderstood that, i thought he flew the ILS/DME approach …
Flyer59 wrote:
i thought he flew the ILS/DME approach
