Question for B73NG Pilots Using GBAS approach
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I don't know a lot about GLS, but I do know a fair amount about LPV. LPV has a complex path data record associated with the database for each LPV IAP. If the database "tanks," so does LPV, and for that matter much of LNAV. ILS, OTOH, is fine because it is derived from modern versions of 1945 radio receivers.
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FlightPathOBN:
That was obvious with my answer in context.
Do I detect a bit of hostility from a "friend?"
So, sir, is GLS totally FMS indepentent?
then why reply to the thread?
Do I detect a bit of hostility from a "friend?"
So, sir, is GLS totally FMS indepentent?
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Oh yes...when they want to have RNP to GBAS, it appears we can get the minima down significantly...
So, sir, is GLS totally FMS indepentent?
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Sorry Terpster, I was being flippant...I should have added some 
GBAS is independent of the FMC much like an ILS. If the aircraft didn’t have an FMC (FedEx B-727) you can fly a GLS approach as the data and correction is delivered from the MMR (as it is with an ILS approach).
The FMC offers two benefits to the GLS approach user (as it does the ILS user), ND Map sequencing and missed approach guidance if the missed approach segment is flown in LNAV.
So if you were operating an FMC equipped aircraft on a GLS approach and had a dual FMC failure, it would not impact the approach.
GBAS is independent of the FMC much like an ILS. If the aircraft didn’t have an FMC (FedEx B-727) you can fly a GLS approach as the data and correction is delivered from the MMR (as it is with an ILS approach).
The FMC offers two benefits to the GLS approach user (as it does the ILS user), ND Map sequencing and missed approach guidance if the missed approach segment is flown in LNAV.
So if you were operating an FMC equipped aircraft on a GLS approach and had a dual FMC failure, it would not impact the approach.
Last edited by FlightPathOBN; 19th Apr 2011 at 17:24.
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Denti,
without going too far into the chart standards, I do note that the ILS plate shows an MDA, while the GLS chart shows a DA.....
In this case i'm not that sure that the obstacle is the limit.
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Well, it is part of the RNAV transition which is as far as i know at least RNP 1 (our FMC flies it as RNP 0.3), however ATC usually turns you to final early which leaves the transition and makes those nice turns around the intended line. Vectors to final are the norm for airline traffic.
Sadly GLS is officially down and not usable for the time being until it is through the whole certification process. I have to add though that EDDW is one of those places we do not visit all that often anyway, other operators use it more often, lufthansa has based the CJ1s of its flying school there.
Sadly GLS is officially down and not usable for the time being until it is through the whole certification process. I have to add though that EDDW is one of those places we do not visit all that often anyway, other operators use it more often, lufthansa has based the CJ1s of its flying school there.
