LNAV/VNAV non-precision approach on Boeings???
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From: on the way...
LNAV/VNAV non-precision approach on Boeings???
Dear colleagues,
Don’t you know, is it necessary to have some special CAA approval to fly LNAV/VNAV non-precision approaches with B737 in UK or another EU countrie?
Don’t you know, is it necessary to have some special CAA approval to fly LNAV/VNAV non-precision approaches with B737 in UK or another EU countrie?
Last edited by relax.jet; 8th June 2008 at 21:12.
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From: USofA
In the US the operator would need to have their respective Ops Specs annotated so as to allow these procedures to be used. This would in turn assure compliance with the specific aircraft and equipment being utilized, i.e., Pegasus, PIP, GPS, Non GPS. Also the training program used to qualify the flight crews. I would imagine something simialr exists in GB as well.
Joined: Mar 2000
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From: Arizona USA
Of course, if we look back in time (say, ten years or so), we find the following...
Lockheed L1011.
Equipped with Honeywell HT9100 dual FMS/GPS units.
Fully certified for, enroute, terminal, approach (...ie; NPA).......and they worked to perfection.
And, still do.
Lockheed L1011.
Equipped with Honeywell HT9100 dual FMS/GPS units.
Fully certified for, enroute, terminal, approach (...ie; NPA).......and they worked to perfection.
And, still do.
Last edited by 411A; 9th June 2008 at 07:54.
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From: Well it's an IRS nowdays, but the AHRS were fun.
LNAV/VNAV approaches fly to a DA (decision altitude) rather than an MDA (Minimum Descent Altitude). I currently fly these approaches under the US FAA part 135 (Gulfstream GIV) and yes the operator has to be approved. Same in other countries too.
Joined: Mar 2001
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From: I wouldn't know.
I guess it depends on the local authority how they handle that stuff. We got minimal training (just flying one LNAV/VNAV or IAN approach during normal SIM checks) and are approved to fly them down to MDA serving as a DA for non precision approaches. Only restriction is that we have to use the autopilot on approaches with an RNP of 0.15 or lower until visual reference is aquired during the approach.
Of course IAN makes it even easier as you fly the NPA absolutely the same way as you do ILSs with the exception that you can only use one autopilot.
Of course IAN makes it even easier as you fly the NPA absolutely the same way as you do ILSs with the exception that you can only use one autopilot.
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From: Sydney NSW
Ht9100
This unit was not specific to the L1011 though. Fitted to a number of a/c including large and small Boeings, some M-Ds and early Airbus. I can't remember exactly raving about it. I have one mid-atlantic airfield in mind that has a non-precision approach with an offset TACAN and an NDB in the most useless place other than to indicate where a decent steak might be had. The approach lights there always looked pink but the tea and banana cake was worth the trip. Without wishing to provoke an A vs B argument the MMI A330 that used to go there always seemed to have a better approach than many.
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From: Wish it was warmer
Just a quick question to the guys approved to fly LNAV/VNAV approaches.
What means do you use to correct for low temperatures during winter operations?
We are not allowed to fly them due to the fact that we are not allowed to do corrections to the vertical profile of the published fms-(fmgc)fixes.
Do you have a specific temp-range you are allowed to fly them, or does the profile change if you put in current temperature of the field in the fms (fmgc)?
What means do you use to correct for low temperatures during winter operations?
We are not allowed to fly them due to the fact that we are not allowed to do corrections to the vertical profile of the published fms-(fmgc)fixes.
Do you have a specific temp-range you are allowed to fly them, or does the profile change if you put in current temperature of the field in the fms (fmgc)?
Joined: Mar 2006
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From: England
Re “…make the height corrections automatically”, but whatever cleverness the software has, it still depends on an accurate input. Similarly, doesn’t the generation of VNAV waypoints also depend on setting the correct QNH.
So VNAV is a more accurate system, but there are just as many if not more opportunities for error; - a need for good crosschecking SOPs and always select EGPWS terrain display on one display.
So VNAV is a more accurate system, but there are just as many if not more opportunities for error; - a need for good crosschecking SOPs and always select EGPWS terrain display on one display.
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From: France
Lnav/vnav
EASA has just published draft material covering approvals for RNP APCH (LNAV/VNAV to RNP 0.3) and for RNP AR APCH (LNAV/VNAV to RNP 0.1 with fixed radius turns in final/missed) See
http://www.easa.eu.int/ws_prod/r/r_npa.php
http://www.easa.eu.int/ws_prod/r/r_npa.php
Thread Starter
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From: on the way...
OUr latest software updates make the height corrections automatically, when we put the aerodrome conditions into the approach section of the FMS....pretty cool. That allows us to use them!
