CessnaLady From Mexico, joined May 2004, 307 posts, RR: 5 Posted (7 years 5 months 1 week 4 days 19 hours ago) and read 2305 times:
Flight AM 108 on Dec/13, on a sparkling-new B73NG (XA-HAM): We took off from MEX (Elevation: 7144 Ft) on this beautiful, clear, no-clouds day... and climbed, climbed, climbed and climbed. 15 minutes into the flight the FP announced we had reached our cruising altitude of 44,000 Ft... And then, just 8 minutes later, (i.e., at 23 minutes after take off), we started descent into GDL (Elevation: 5,100Ft), where we landed exactly 21 minutes later. We were airborne for exactly 44 minutes.
Does it make sense to take the a/c to such altitude for 8 minutes just to drop down again? I'd really like to learn... why would you do that?
XA744 From Mexico, joined Mar 2004, 734 posts, RR: 3 Reply 1, posted (7 years 5 months 1 week 4 days 18 hours ago) and read 2286 times:
Well, I am not a pilot, but could it have been a jet stream unusually traveling at between 25k to 35k ft ?
I was once on board a MAS 777 from EWR to DUB, and just when flying over Austria, the pilot requested ATC in VIE authorization to climb from 37,000 to 45,000 ft due to a jet stream that was on our path. I was in the cockpit and got this explanation from the FO.
Regards
No matter how you fly...just never get your wings clipped !
StuckinMAF From , joined Dec 1969, posts, RR: Reply 3, posted (7 years 5 months 1 week 4 days 18 hours ago) and read 2267 times:
Hmm, not sure why it was so high either, but I know this is a typical Southwest flight profile in Texas, too. Going from MAF to DAL, HOU, or ABQ, we'll climb like crazy, level off at FL3x0 for about 10 minutes (A little longer to HOU), then begin decending. I guess that margin of efficiency at the high cruise altitude and the long decent makes up for the time spent climbing!
Ghost77 From Mexico, joined Mar 2000, 5128 posts, RR: 53 Reply 5, posted (7 years 5 months 1 week 4 days 3 hours ago) and read 2075 times:
Quoting EGTESkyGod (Reply 4): Sorry to be pedantic, but FL44 is 4,400ft, so 44,000ft is FL440.
Sorry to be pedantic, but technically FL44 is not 4,400ft, that doesn't exist... ATC never mention you to decrease altitude to FL44.
Cessnalady - I'm sure this are efficiency test flights... you climb higher and faster with the B73G cruise faster and descent burning the less fuel... you gain more speed descending, save time and fuel!!!
ghost77 APM
Ricardo Morales - flyAPM - ¡No es que maneje rapido, solo estoy volando lento!
Pr1268 From United States of America, joined Dec 2003, 232 posts, RR: 0 Reply 6, posted (7 years 5 months 1 week 4 days 3 hours ago) and read 2056 times:
Just curious, I thought that the certified ceiling of the 737NG was FL410 and the 777 FL431 (43,100) feet (couldn't find those on Boeing's site, but I vividly remember reading those in a Jane's Aircraft book).
Granted, the planes are usually CAPABLE of flying higher than their certified ceiling, but doesn't that require some kind of bureaucratic process (variance from the airline's SOP or Pilot's Operational Handbook [POH])?
Also, don't these planes generally perform like crap at these rarified altitudes? I remember reading the TWA incident from April 1979 when the crew tried to extend the flaps 1 notch at FL390 (an unusually high altitude for the 727) to try to enhance the maneuvering performance.
Any others' thoughts?
The only time an aircraft has too much fuel is when it is on fire.
Pr1268 From United States of America, joined Dec 2003, 232 posts, RR: 0 Reply 7, posted (7 years 5 months 1 week 4 days 3 hours ago) and read 2038 times:
As for the really high short flights (reply 3), I've read that it is actually in the best interest of fuel economy to use the "bullet" profile (take off, climb unusually high, then descend) for short flights because the extra fuel used to climb higher is somehow offset by the savings of a longer, low-power descent.
Many South American airlines do it this way - LB, LA, PL, etc. especially on short-haul flights of 30 min - 2 hrs.
I did AUS-LAS on WN in May 2003 at FL390 - very nice flight indeed, plus my first flight in a 73G. Even when I did DAL-HOU on WN in 1999, we ascended all the way to FL330 for a 45 min. flight.
But, even WN can't get above FL250 even if they tried on a HOU-AUS flight these days (typically 25-28 minutes flying time).
The only time an aircraft has too much fuel is when it is on fire.
FLY2HMO From , joined Dec 1969, posts, RR: Reply 8, posted (7 years 5 months 1 week 4 days 2 hours ago) and read 2020 times:
Quoting Pr1268 (Reply 7): As for the really high short flights (reply 3), I've read that it is actually in the best interest of fuel economy to use the "bullet" profile (take off, climb unusually high, then descend) for short flights because the extra fuel used to climb higher is somehow offset by the savings of a longer, low-power descent
Correct. They'll usually wait until the last possible minute to descend, and it will be a steep descent so the plane basically glides down with engines almost at idle.
Geo772 From United Kingdom, joined Jul 2004, 497 posts, RR: 0 Reply 9, posted (7 years 5 months 1 week 4 days 1 hour ago) and read 1988 times:
Everytime I've flown on a 73G it has involved a cruise above 40,000ft. The shortest flight was about an hour and ten minutes and the longest a little under 2 hours.
In days gone by it was quite common for flight crews to fly at a constant power setting and just steadily climb during the flight. The BAC1-11 benefitted from this and especially the VC10 which could break through the 40,000ft barrier.
Flown on A300B4/600,A319/20/21,A332/3,A343,B727,B732/3/4/7/8,B741/2/4,B752,B762/3,B772/3,DC10,L1011-200,VC10,MD80,1-11
Pr1268 From United States of America, joined Dec 2003, 232 posts, RR: 0 Reply 10, posted (7 years 5 months 1 week 4 days 1 hour ago) and read 1962 times:
Replying to Geo772 (Reply 9): The Concorde did it this way, if I remember reading about this in some article. The Concorde would flatten its ascent (don't dare call it levelling off) at around FL520 or so and Mach 2.01, and climb at around 80-100 fpm x 90 minutes or so, then begin its descent from around FL600.
The only time an aircraft has too much fuel is when it is on fire.
N1120A From United States of America, joined Dec 2003, 25852 posts, RR: 79 Reply 11, posted (7 years 5 months 1 week 4 days ago) and read 1936 times:
Quoting CessnaLady (Thread starter): the FP announced we had reached our cruising altitude of 44,000 Ft...
No you didn't. The 73G's max certified altitude is FL410, 41,000 feet.
Quoting Ghost77 (Reply 5): Sorry to be pedantic, but technically FL44 is not 4,400ft, that doesn't exist... ATC never mention you to decrease altitude to FL44.
There is no FL44, it is 4,400 feet or FL440 which is 44,000 feet.
Mangeons les French fries, mais surtout pratiquons avec fierte le French kiss
Juventus From United States of America, joined Dec 2004, 2835 posts, RR: 2 Reply 12, posted (7 years 5 months 1 week 3 days 20 hours ago) and read 1868 times:
Sometimes pilots accept higher altitudes if ATC offers them a shor-cut.
Adriaticus From Mexico, joined May 2004, 1112 posts, RR: 21 Reply 13, posted (7 years 5 months 1 week 3 days 2 hours ago) and read 1778 times:
Quoting N1120A (Reply 11): No you didn't. The 73G's max certified altitude is FL410, 41,000 feet
I don't think it was you, but her who was on board that aircraft. You are nobody to discredit her saying.
Quoting Ghost77 (Reply 5): I'm sure this are efficiency test flights... you climb higher and faster with the B73G cruise faster and descent burning the less fuel... you gain more speed descending, save time and fuel!!!
Quoting XA744 (Reply 1): authorization to climb from 37,000 to 45,000 ft due to a jet stream that was on our path
I concur with Ghost and XA744. Our own a/c ver often do this maneuvers for the same reasons.
Luis777 From Mexico, joined Aug 2004, 89 posts, RR: 0 Reply 16, posted (7 years 5 months 1 week 1 day 18 hours ago) and read 1622 times:
Impossible for a 737-700 to flight above FL410 on a regular flight, I don't want to discredit anyone, It's clear, the flight envelope for a 737 NG is 41,000 ft and all the 737 NG pilots know that and never would fly their plane above its limitations, maybe it could fly higher but only on test flights made by Boeing, It's possible that the flight attendant made a mistake when she had to announce the flight level. She understood FL440 instead FL410.
N1120A From United States of America, joined Dec 2003, 25852 posts, RR: 79 Reply 17, posted (7 years 5 months 1 week 1 day 18 hours ago) and read 1619 times:
Quoting Adriaticus (Reply 13): I don't think it was you, but her who was on board that aircraft. You are nobody to discredit her saying.
This has nothing to do with discrediting anyone, just to say that she may be confused. The maximum certified altitude for any 737NG aircraft (737-600/700/800/900) is FL410. This is 2000 feet higher than the A32S and 4000 feet higher than the 737Classic. If you go above FL410, you are in violation of the law, your insurance policy and good sense.
Mangeons les French fries, mais surtout pratiquons avec fierte le French kiss
Gigneil From United States of America, joined Nov 2002, 16215 posts, RR: 88 Reply 18, posted (7 years 5 months 1 week 1 day 17 hours ago) and read 1585 times:
Quoting Adriaticus (Reply 13): I don't think it was you, but her who was on board that aircraft. You are nobody to discredit her saying.
Well, except it doesn't matter who was on board the aircraft. The plane's service ceiling is 41,000 feet. It is illegal to operate it higher than that.
Hence, the plane wasn't there. Certainly not 44,000.
CessnaLady From Mexico, joined May 2004, 307 posts, RR: 5 Reply 19, posted (7 years 5 months 1 week 1 day 1 hour ago) and read 1506 times:
Now the fun has started...
Quoting Luis777 (Reply 16): Impossible for a 737-700 to flight above FL410 on a regular flight
Not impossible. We were there.
Quoting Luis777 (Reply 16): It's possible that the flight attendant made a mistake when she had to announce the flight level. She understood FL440 instead FL410.
.
The FP, not the FA, made the announcement... Together with a series of remarks pointing out cities (like Toluca and Morelia), external temperature (-64°C), and landscape features. As I said before, it was a remarkably clear day.
Quoting N1120A (Reply 17): If you go above FL410, you are in violation of the law,
Nice and sharp dictum!!... And which jurisdiction is this that you seem to know so well? (Just FYI, we were in Mexican airspace).
Quoting Gigneil (Reply 18): It is illegal to operate it higher than that.
Hence, the plane wasn't there.
I should not even answer this stupid sophism (Reminded me KL 007 shouldn't have been where it was )... But indeed my plane was there...
Or go tell the FP his altimeters were off for a few thousand feet!!
Airlinerfreak From , joined Dec 1969, posts, RR: Reply 20, posted (7 years 5 months 1 week 1 day 1 hour ago) and read 1499 times:
Well often times through Mexico you find turbulent weather. I have found in on such flights from PVR-MEX multiple times. We have often had to make deviations or fly above the storms so weather could always be a possibility.
N1120A From United States of America, joined Dec 2003, 25852 posts, RR: 79 Reply 21, posted (7 years 5 months 1 week 23 hours ago) and read 1461 times:
Quoting CessnaLady (Reply 19): And which jurisdiction is this that you seem to know so well? (Just FYI, we were in Mexican airspace).
It doesn't matter what airspace you were in. The 737NG is certified for a max altitude of 41,000 feet. That is what it is designed for, that is what Boeing recommended to all of the regulatory bodies and it is what the aviation authorities have certified it for. This is the same in Mexico as it is anywhere else
Quoting CessnaLady (Reply 19): Or go tell the FP his altimeters were off for a few thousand feet!!
Adriaticus From Mexico, joined May 2004, 1112 posts, RR: 21 Reply 22, posted (7 years 5 months 1 week 23 hours ago) and read 1444 times:
N1120, Gigneil and CessnaLady have gone personal here. I think the point of the original question has been answered, made and well taken... Climb high to glide down with overall greater fuel efficiency, and/or avoidance of turbulencies / jet streams.
With reference to Boeing's manufacturer recommendation becoming the law everywhere... I wouldn't take that for granted. I am indeed an attorney for an airline, and I can attest there are many loopholes and omissions in that respect in many regulatory systems. Saying "it's the Law" just because Boeing "recommended" something, is, to put it mildly, far-fetched.
N1120A From United States of America, joined Dec 2003, 25852 posts, RR: 79 Reply 23, posted (7 years 5 months 1 week 22 hours ago) and read 1433 times:
Quoting Adriaticus (Reply 22): Saying "it's the Law" just because Boeing "recommended" something
That is not what I am saying. I was stating that, in addition to FL410 being the max certified altitude of the 737NG by any regulating body in the world, it was also Boeing's recommendation.
Quoting Adriaticus (Reply 22): I can attest there are many loopholes and omissions in that respect in many regulatory systems.
Max certified flight altitude is not one of them. It is not only in contravention of aviation regulations all over the world, it is also going to lose an airline their insurance policy on the aircraft. Further, given that AM leases many of their 73Gs, it will break their lease contract.
Quoting Adriaticus (Reply 22): N1120, Gigneil and CessnaLady have gone personal here.
This is nothing personal, it is a correction of a mistake.
Mangeons les French fries, mais surtout pratiquons avec fierte le French kiss
Nosedive From , joined Dec 1969, posts, RR: Reply 24, posted (7 years 5 months 1 week 22 hours ago) and read 1419 times:
Quoting Adriaticus (Reply 22): Saying "it's the Law" just because Boeing "recommended" something, is, to put it mildly, far-fetched.
It also is a great opening for a lawsuit!
25 Ghost77: Well, it's then time and place to disclose names, hours, flights and dates, Luis777 is a first hand ground instructor and responsible for all those A
26 Gigneil: I'd be pleased to. As Ghost suggested, it would be awfully nice to know the name of said pilot that would risk his career, your lives, and Aeromexico
27 BBJII: The BBJ (which is a 700series) has a optimum Altitude of FL440. We normally fly @ FL390 and not above, unless we van get a good tail wind to save fue
28 Luis777: I need proves, did you read the altimeters and were inside the cockpit?, besides maximum certified altitude is determined during certification and is
29 N1120A: According to the FAA, all 737s, including the 737-700IGW on which the BBJ1 is based, have a maximum certified altitude of FL410. Other than the stren
30 MTY2GVA: If it happened congratulations your alive you should make a T-shirt that says " I survived flying at FL440 on a 737-700"
31 Tornado82: They didn't kill anybody on the ground in that crash, and since when did they get above FL410 either?
Sponsor Message: 
From Mexico, joined May 2004, 307 posts, 
From , joined Dec 1969, posts, 
From United Kingdom, joined Jun 2005, 1686 posts, 
From Venezuela, joined Aug 2004, 2516 posts, 
)... But indeed my plane was there... 
Printer friendly format 
