737 at 41,000 ft

[chrishowley]

Yesterday I flew from ORD to LGA and the captain announced that we were cruising at 41,000 ft which is the only time I can remember such a high figure being quoted.

This leads me to two questions:

1. What is the maximum cruising altitude of a 737?. .2. I always thought that higher was more efficient so if jets can fly at this height why do they not do so more regularly?

[Hand Solo]

I think the new generation 737s can reach 41000ft, but the older ones certainly can't. I believe some 767s can go that high as well. The choice of a cruising altitude has a lot of factors involved. Whilst its generally better to go higher, you may be too heavy to reach that level, run into less favourable winds or it may just be taken already by another aircraft on the same route to name just three.

[Stampe]

Correct the 737NG max.alt. is 410 I only have experience on the series 800 which had to be quite lightly loaded to get there but guess the 6/700 series would get there more often.The NG,s have a new wing compared to the earlier series which gives them a better altitude capability and higher cruising mach number of just a tad under Mach 0.8 as against about 0.73 of the earlier series. I,ve moved on recently but an excellent commercial aeroplane a real money maker.

[ 28 January 2002: Message edited by: Stampe ]</p>

[chrishowley]

Many thanks for the info.

[christep]

I've been at 41,000 in a CX 777 as well on the "parcel" run from SIN to HKG which they do with a load of stuff in the hold for ?DHL? and no more than 40-odd pax (and about one stewardness between two pax <img src="smile.gif" border="0"> ). I guess that day they didn't have much in the hold so were running very light.

[Call_Belle]

Often do transatlantic flights on EI A330's at 41,000 ft

[Pax Vobiscum]

Recently flew London (Stansted) to Aarhus - 41000 out and 40000 back (on 737-800). Impressive views on a lovely clear day. I guess ATC like to get them high out of the way of other traffic, but I wonder about the fuel efficiency of all that climbing on a relatively (75 min) short flight.

Pax Vobiscum

[Hand Solo]

Generally speaking the higher you go the less you burn, otherwise we wouldn't do it. Even on short sectors.

[chrishowley]

yeah it is a good view from up there! Even better from Concorde at FL560 mind you!

Climbing is not usually an issue because - you get the benefits of flying at higher altitude (after all if you've climbed to FL360 anyway whats the problem with an extra 5000ft). Plus what is costs you in the climb you get most of back in the descent.

[atco-matic]

The highest I have ever seen a civil airliner cruising at was a Cargolux 747-400 at 45,000ft!! When we asked the pilot, it was of course empty.

Aside from this, the two highest passenger liners I have seen are a BA 777 and South African 747-SP which were both cruising at 43,000ft. Both were near the end of their flight.

One thing you didn't mention about cruising so high is that you are more likely to get direct routeings at these altitudes (especially in european airspace) when you're higher than everybody else.

[Stampe]

767 has a ceiling of 43000 but nowadays my company require flightdeck crew to wear oxygen above 41000 as a precaution due to the very low time of useful consciousness in the event of sudden decompression so I and most of my colleagues don,t go there anymore.Also radiation is at its highest around FL430 so another good reason for staying below 40000ft I,ve already spent to much of my life up in those regions!!.I remember well flying south down the eastern seeboard of the the USA many years ago and seeing a Lear opposite direction way above us at I believe 54000 that really is impressive in a non military private owners machine.

[Kerosene Kraut]

Some Bizjets cruise as high as FL510.