737 glide ratio and speed
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737 glide ratio and speed
I have been trying unsuccessfully to find the boeing 737 classics glide ratio and speed (depending on weight for sure) . Please somebody direct me to where in the documentation to find it. i do know that in the QRH below 270 speed 300
and 275 above FL 270 is recommended however are those speed for glide ratio or increasing probability of successful starts.
i have seen some answers in previous thread however i still dont know where in the docs it is indicated
mamad
and 275 above FL 270 is recommended however are those speed for glide ratio or increasing probability of successful starts.
i have seen some answers in previous thread however i still dont know where in the docs it is indicated
mamad
Last edited by mamad; 19th Jul 2012 at 19:45.
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A rule of thumb is 2 miles per 1000 and 5000 for a 360 degree turn at min clean (210/220) which is as good as best lift /drag ratio that you will get following a double hush. Aim to be be at 4 miles at 2500 agl on the centreline at F5 170(180) there take flap 10 inbound and when certain you will make the field take gear down and flap 15.
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Can't remember it absolutely, but is there not a relationship between 'best angle climb speed' and best glide speed? This is slower than 'best ROC speed' so I think this will be closer to best glide. Someone will know.
I remember reading somewhere recently that glide ratio of big jets had hovered around 1:11 for a long time which roughly matches the 2 miles per thousand feet rule of thumb. If you have done any gliding you will know that weight does not negatively impact glide ratio, but will of course increase rate of descent and best speed. Not a lot of time is spent practicing for loss of all engines, which makes Sully's effort all the more impressive.
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Lederhosen - (stopped wearing mine back around 1969).
18:1 767. Boeing data
757 slightly better - unknown amount
737W/757W approx. 19.5:1 personal observation using sink rates, TAS, etc, etc.
News report said 787 is over 21:1, and maybe 22:1.
Best glide speed is typically listed in the dual engine flameout charts.
Higher speeds mentioned by OP are for restarts, glide speed, as Framer noted, is in the low 200's depending upon aircraft model and actual gross weight.
Idle descents probably have slightly better than dead stick performance. Considering descents are 250 KIAS the gliding performance might be very similar to dead sticking at 220 KIAS(+/-). Verifying you basic performance by cross-checking if your target is raising, dropping, or staying steady in your window screen is learned before you solo. Sully mentions the decision that he wouldn't make TEB was immediate as he saw it rising in his windshield.
18:1 767. Boeing data
757 slightly better - unknown amount
737W/757W approx. 19.5:1 personal observation using sink rates, TAS, etc, etc.
News report said 787 is over 21:1, and maybe 22:1.
Best glide speed is typically listed in the dual engine flameout charts.
Higher speeds mentioned by OP are for restarts, glide speed, as Framer noted, is in the low 200's depending upon aircraft model and actual gross weight.
Idle descents probably have slightly better than dead stick performance. Considering descents are 250 KIAS the gliding performance might be very similar to dead sticking at 220 KIAS(+/-). Verifying you basic performance by cross-checking if your target is raising, dropping, or staying steady in your window screen is learned before you solo. Sully mentions the decision that he wouldn't make TEB was immediate as he saw it rising in his windshield.
Last edited by misd-agin; 22nd Jul 2012 at 14:04.
misd-again thanks for your input, the improvement in glide ratio from the classic to the NG and additionally with winglets makes sense. The 787 I doubt very much I shall ever experience from front left.
But with respect if you cannot get one or more engines started, flying around 210 knots and planning on two miles per thousand feet is about as much as you need to know and will have the capacity for while you try and manage the other priorities.
Extensive gliding experience by the way has helped a number of crews to a better conclusion, the Air Canada 767 (Gimli glider) and Air Transat A330 in the Azores being two good examples as well as of course Sully.
I have been a TRI on the 737 for a while and cannot ever remember our manuals containing dual engine flameout charts. (We do have an in-flight start envelope.) I may be having a senior moment, but I think most people will struggle to find the data you suggest. Can you post us a copy to tweak the old grey cells.
But with respect if you cannot get one or more engines started, flying around 210 knots and planning on two miles per thousand feet is about as much as you need to know and will have the capacity for while you try and manage the other priorities.
Extensive gliding experience by the way has helped a number of crews to a better conclusion, the Air Canada 767 (Gimli glider) and Air Transat A330 in the Azores being two good examples as well as of course Sully.
I have been a TRI on the 737 for a while and cannot ever remember our manuals containing dual engine flameout charts. (We do have an in-flight start envelope.) I may be having a senior moment, but I think most people will struggle to find the data you suggest. Can you post us a copy to tweak the old grey cells.
Last edited by lederhosen; 22nd Jul 2012 at 15:25.
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Max landing weight, dual engine glide speeds, for 5 different types, are between 215-240 kts.
All of our a/c, except one, publish dual engine flameout glide speeds.
18:1 is 3 n.m. per 1,000. I recall reading that Airbus recommends 2.5 per thousand.
If you're a TRE you can do this is the sim - 250 kts at 10,000'/40 DME or 250 kts @ 5,000'/20 DME(typical arrival 'energy' gates). IMO it's an excellent demonstration of the aircraft's gliding ability and energy/drag management.
It's nice to know, at least no wind, that you can deadstick from the descent profile and might, or will, reach the airport. If you're below the profile you also know instantly, as Sully did, that trying to glide to X is impossible.
Air Transat lost the second engine at approx. 34,500 65 n.m. from the airport, had to do 360's, and was still fast and high on final so 2 n.m per thousand is more than enough altitude/distance.
All of our a/c, except one, publish dual engine flameout glide speeds.
18:1 is 3 n.m. per 1,000. I recall reading that Airbus recommends 2.5 per thousand.
If you're a TRE you can do this is the sim - 250 kts at 10,000'/40 DME or 250 kts @ 5,000'/20 DME(typical arrival 'energy' gates). IMO it's an excellent demonstration of the aircraft's gliding ability and energy/drag management.
It's nice to know, at least no wind, that you can deadstick from the descent profile and might, or will, reach the airport. If you're below the profile you also know instantly, as Sully did, that trying to glide to X is impossible.
Air Transat lost the second engine at approx. 34,500 65 n.m. from the airport, had to do 360's, and was still fast and high on final so 2 n.m per thousand is more than enough altitude/distance.
Last edited by misd-agin; 22nd Jul 2012 at 21:11.
It's nice to know, at least no wind, that you can deadstick from the descent profile and might, or will, reach the airport. If you're below the profile you also know instantly, as Sully did, that trying to glide to X is impossible.
Whereas what is needed in the simulator is practical flying skills such as practicing strong crosswind landings, dark night black hole approaches sans glide slope guidance, raw data instrument approaches manually flown and of course dead stick landings from high altitude. High altitude and circuit altitude stall recoveries require manual flying skills and these need to be practiced, too.
Unfortunately, the box ticking magenta line automatic pilot brigade have the upper hand in choosing what simulator practice has the priority with the lessons of the Air France A330 accident having no impact on what is currently taught or practiced in the simulator.
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I flew the B737 100, 200 and 300 before going to the B757. We did six legs a day so got idle descents down really good. We did high speed down to 10 at 2 times the altitude at 320 knots, then 250 to the approach point at 3 times the altitude then decreased speed for approach and most of us could do it 95 % of the time with no problem without using power from FL350 to 1000 ft. It doesn't happen that way much now with the Riddle pilots flying.
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It doesn't happen that way much now with the Riddle pilots flying.
They are talking about engine out glide speed not idle speed descent ,you muppet.
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df,I know you are not in China but what makes you so angry about simple things like 737 descents? Engines out or idle. Maybe an anger management course is in your future. Did you take the quick course with Daddy's help?
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Sorry about previous answer (deleted), I was confused with max range - max endurance.
Max glide occurs at max L/D which occurs at Vdmin. Vdmin is also the speed for max endurance (jets).
Holding tables all engines in the QRH are based on the following, higher of:
-Man speed.
-Max endurance speed.
You can use those speeds as glide speeds.
Max glide occurs at max L/D which occurs at Vdmin. Vdmin is also the speed for max endurance (jets).
Holding tables all engines in the QRH are based on the following, higher of:
-Man speed.
-Max endurance speed.
You can use those speeds as glide speeds.
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Whereas what is needed in the simulator is practical flying skills such as practicing strong crosswind landings, dark night black hole approaches sans glide slope guidance, raw data instrument approaches manually flown and of course dead stick landings from high altitude. High altitude and circuit altitude stall recoveries require manual flying skills and these need to be practiced, too.
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Thank you guys for all this infos
i guess i will just stick with the 210 2nm per 1000 ft answer
eventhough that would have been nice to have a reference
mamad
i guess i will just stick with the 210 2nm per 1000 ft answer
eventhough that would have been nice to have a reference
mamad
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mamad, 2X Alt will work just fine and is conservative so you can push it a bit if you want. The 737 100 and 200 aircraft didn't have high bypass engines so the idle thrust vs no thrust descent wasn't a lot different.
We practiced dead stick landings in the 737 in the sim and the descent was just slightly steeper. We would just stay a dot and a half above the glide slope or if no glide slope stay slightly high and dirty up to final flaps at 100 ft or so with a little extra speed to get you on a normal touchdown profile. The 737 800 might be closer to 2 to 1 than we were, 2.5 to 1.
We practiced a lot of dead stick landings flying business jets when empty in Lear Jets and Citations to sharpen our skills. If you ever become a Sully one day you will know what to do.
Going from a pilot mill to the right seat is great but you miss out on all the learning about flying you get from doing it a few years in the real world, not with a flight instructor and a syllabus.
We practiced dead stick landings in the 737 in the sim and the descent was just slightly steeper. We would just stay a dot and a half above the glide slope or if no glide slope stay slightly high and dirty up to final flaps at 100 ft or so with a little extra speed to get you on a normal touchdown profile. The 737 800 might be closer to 2 to 1 than we were, 2.5 to 1.
We practiced a lot of dead stick landings flying business jets when empty in Lear Jets and Citations to sharpen our skills. If you ever become a Sully one day you will know what to do.
Going from a pilot mill to the right seat is great but you miss out on all the learning about flying you get from doing it a few years in the real world, not with a flight instructor and a syllabus.
