In relation to AirAsia flight QZ8501 officials have been quoted as saying:

"It is not normal to climb like that. It's very rare for commercial planes, which normally climb just 1,000 to 2,000 feet per minute. It [climbing at 6,000 ft per minute] can only be done by a fighter jet."

Two parts of that statement struck me:

  1. The rate of 1,000 to 2,000 feet per minute is stated as "normal", not "maximum"
  2. The claim that only fighter jets can climb at 6,000 feet per minute.

My question is then:

  1. What is the maximum climb rate that an AirBus A320-200 such as the one involved in this incident could achieve with out stalling? (Including configurations and operations outside of "normal")
  2. If it is less than 6,000 feet per minute on the A320-200 can any commercial passenger carrying aircraft in operation today exceed 6,000 feet per minute? (I'd assume Concorde could, but that's no longer in operation)
  • $\begingroup$ Was the high climb rate the result of pilot control input, or just a violent updraft? $\endgroup$ – DJohnM Jan 29 '15 at 21:18
  • $\begingroup$ @User58220 Impossible to answer until the FDR data is released and the investigation concluded. $\endgroup$ – Simon Feb 5 '15 at 20:15

There's a lot of nonsense being banded about regarding this flight.

First up, we are not talking about sustained, powered climb rates. If you're travelling at Mach 0.85 and pull up vertically, in theory (if your plane didn't break) you'd climb at an initial rate of nearly Mach 0.85 (your original speed minus the airspeed loss when pulling up).... That's near enough 57,000 feet/minute.

If you're at high speed and willing to trade speed for altitude, an Airbus A320 is physically capable of climbing at much higher rates than 6000 feet per minute.... At least until it runs out of airspeed.

A fighter is the only aircraft which would be likely to perform a sustained 6000ft/minute climb rate in normal use, but they're also capable of much higher rates of climb.

The maximum rate of climb you'd see in an A320 in normal use is in the 2000 ft/min range, but that's because it's the highest reasonably efficient rate of climb. That's not the maximum the aircraft is capable of under power (which is more in the region of 4000 ft/min), and is absolutely no indication of that maximum unsustained climb rate.

It would eventually stall at any unsustainable rate of climb, but then again, so would any aircraft even at a sustainable rate... Keep climbing and before too long you run out of atmosphere.

Either way, there is nothing to say that climbing above the sustained climb rate for an aircraft is unsafe or, necessarily, unusual. You trade airspeed for altitude, sure, but if you need to be higher at that moment in time, there's plenty of time to accelerate again later.

From Airlines.Net:

The three are roughly the same at 10,000', at about 2500 fpm. (Maybe a bit more for a light A319, and less for a full A321)

Normal climb rates from 10,000' to about 30,000 are as follows:

A319, 3000 fpm to about 1500 at 30,000'

A320, 2200 fpm to about 1000 at 30,000'

A321, 1400 fpm to about 500 at 30,000'

TL;DR - The official is spouting nonsense s/he doesn't understand. A fighter is the only aircraft likely to be able to (or wish to) climb at a 6000 ft/minute SUSTAINED climb rate, but almost any aircraft can climb at that rate for brief durations in a zoom climb - converting airspeed/momentum to altitude

  • $\begingroup$ Presumably in sufficiently unusual circumstances you could trade speed for altitude and then deploy flaps/slats to avoid a stall once the speed dropped low enough too. $\endgroup$ – Flexo Jan 25 '15 at 3:06
  • $\begingroup$ There are twin-jet airliners (757/767, A330) that can sustain climb rates upwards of 3000 fpm when at light weights, but this is also during the takeoff climb, at much lower altitudes. $\endgroup$ – UnrecognizedFallingObject Jan 25 '15 at 3:07
  • $\begingroup$ They can, but not even close to 6000 $\endgroup$ – Jon Story Jan 25 '15 at 3:10
  • $\begingroup$ Note that these are calm-air climb rates. If you get yourself stuck in the core of a thunderstorm, you might see 5000 fpm of climb just from an updraft. $\endgroup$ – Mark Jan 25 '15 at 6:17
  • 1
    $\begingroup$ @Jon Story -- actually, there are pilots mentioning 4500-5000 fpm climb rates in light (no pax) 757s on climbout... $\endgroup$ – UnrecognizedFallingObject Jan 25 '15 at 6:21

IMHO Weather is main thing to blame

There are many things contribute to an air plane lifting force during a climb;

1) The plane speed Faster speed higher lifting force.
Remember Winds also makes the plane's speed slower/or faster

2) Air density: Higher latitude thinner the air : lower lifting force lower Storm blow such as in a whirlpool can cause low pressure/thin air space: lower lifting force

3) Climb angle: Stiffer the angle or "more vertical": less lifting force;

Winds may change directions make climb angle virtually- become more vertically : hence less lifting force

So it still a guess, the plane would be ok if it perform the same climbing in normal weather; however in a violent storm, you couldn't tell what would happen.

So it leaves my own question on this matter : If pilot can manually fly the plane, how could he/she trained in such situation ?

Something about me:

I know nothing about airplane neither being pilot, but I know little in physics

  • $\begingroup$ Hi, Welcome to Aviation SE! If you have a new question, please ask it was a new question rather than putting it in an answer to another question. $\endgroup$ – reirab Jan 29 '15 at 19:25
  • $\begingroup$ As far as wind is concerned, it doesn't really end up affecting climb rates (except for updrafts, downdrafts, and brief changes due to changing wind speeds.) Aircraft are flown at a given airspeed, not at a given ground speed. Thus, the speed of air over the wings will be the same regardless of whether the aircraft is flying it head wind, tail wind, or no wind. The speed over ground will vary, but this this does not affect the climb rates. $\endgroup$ – reirab Jan 29 '15 at 19:33
  • $\begingroup$ As far as climb angle is concerned, it's a little more complicated than that. Up to the critical angle of attack, increasing the angle of the wings relative to the air flow over the airframe will actually increase the lift produced by the wing. This effect will generally dominate the loss due to the lift force no longer being exactly perpendicular to the ground. In the short term, pitching up can also allow you to trade momentum for altitude, which can temporarily result in very high climb rates until you run out of momentum to trade. $\endgroup$ – reirab Jan 29 '15 at 19:42

Considering the Vne of an a320 is about mach 0.9, theoretically if you were travelling at Vne and were to pull back in to the vertical and still be pushing mach 0.75 by the time you reached the vertical, a climb rate of 50,000 feet per minute is momentarily possible.

  • $\begingroup$ This does not add anything that existing answers don't already cover. $\endgroup$ – fooot Jul 12 '16 at 16:38

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