When I took delivery of a new Cessna 182T last year, I did a test flight for certification purposes. During the test flight we had to perform a power off stall but that didn't go as planned as it was simply impossible to stall. What happened is this: when the airspeed dropped well below the power off stall speed we simply started to sink slowly with a nose-high attitude at about 35 KIAS. This "mushing" went on for what seemed ages before I eventually applied power and pushed the nose down to gain airspeed again. We tried it again after that and the same thing happened. I had an instructor with me who has thousands of hours in a C172 and he had never experienced something like this before.

The odd thing is that this only happened during that flight. During later flights this didn't occur anymore.

There was a passenger in the back seat, fuel tanks only half full so the CG was more aft than usual, but well within limits

Ever since that flight I've wondered:

  • What could cause this to happen? (My guess is it is CG related)

And most importantly:

  • If I would have continued this "mushing" flight, would it be possible to have entered a flat spin or a simple "drop out of the sky" like the infamous Air France 447?
  • 2
    Did you happen to notice your trim setting? It is possible that an extreme down-trim setting could make it harder to stall the plane. Given that your CG may have been slightly aft, you may well have had more nose-down trim than usual. – abelenky Dec 18 '13 at 17:17
  • That's a very good point. I didn't consider this to be a factor. – Philippe Leybaert Dec 18 '13 at 17:20
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    I flew a Rallye 100 & 220 for many years which had slats, and stalling them (as opposed to the mushing you describe) required an almost aggressive entry. – copper.hat Feb 10 '15 at 6:34
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    I think you are confusing a departure (OCF) with a stall. You are out of control the moment that normal control inputs result in unexpected results. IE, when a wing rolls off, or the nose suddenly drops during a stall. However, many aircraft are capable of remaining controllable while exceeding their critical AoA in a stall; therefore, you cannot determine a stalled condition based solely on the responsiveness of the controls. Mushing may very well be a stalled condition, and I'd argue that if you pulled the stick back and the nose didn't accordingly track up that you were technically OCF. – Rhino Driver Aug 5 '15 at 3:13
up vote 23 down vote accepted

I think this is more common than you might think in a C182. The 182 is much more nose-heavy than a 172 (which is particularly noticeable in the flare) and this seems to limit the amount of upward pitch authority the elevator has at low speeds. The only stalls I've done in a 182 are much as you described - you can hold full back-elevator and you just sort of sit there sinking.

Spinning could be an issue if it becomes uncoordinated, but a 182 is a very stable airplane and unlikely to enter a flat spin unless the CG is beyond the aft limit or severely uncoordinated. Perhaps someone else can weigh in further on that possibility, though.

  • 4
    I have the same experience in the Diamond DA20-A1, it's virtually impossible to stall by reducing power and maintaining altitude (keeping the stick full aft, it'll buffet and start to descend, but not enter a full stall), and will require quite the manhandling to enter a spin. – falstro Dec 17 '13 at 21:56
  • Same experience in the C182; it's also much the same story in the AG-5B Tiger and DA-40. All three have pretty favorable stall characteristics, and a mid/forward CG in the 182 does still leave it pretty nose-heavy. – egid Dec 17 '13 at 22:12
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    I wouldn't call this behavior favorable. A nose drop when a stall occurs will break the stall by itself and would be more obvious (and beneficial) to the pilot than mere sinking in a nose-high attitude. At low altitude the pilot could very well be unaware of the stalled condition and wouldn't see the ground approaching because of the attitude. – Philippe Leybaert Dec 17 '13 at 22:46
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    Piper PA28 (and to lesser extent the PA32) exhibit similar behaviour. They just kind of descend while fluttering slightly. Not at all like the HARD break the C172 I trained in did. – Brian Knoblauch Dec 17 '13 at 22:48
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    @PhilippeLeybaert By favorable, I think egid was mainly referring to how stable and controllable the plane is in a stall vs. wanting to go into a spin. The Cirrus SR20 G2 I did my private in always dropped a wing, which was decidedly unfavorable. Whether or not a break is preferable, I guess is a matter of opinion. – Bret Copeland Dec 17 '13 at 22:58

Some aircraft don't have enough elevator authority to enter a real stall if the have a nose heavy CG. The wing fails to achieve the required angle of attack, and the plane mushes.

The solution for these kids of planes is not to enter the stall from MCA, as is typically taught. Rather, enter from straight and level flight at Vx, and break into a full stall by sharply moving the yoke to its full aft position. This should result in a significant nose-up attitude and exceed the critical angle of attack, and you will see and feel a sharp break. Remain coordinated throughout the maneuver, and recover by releasing back pressure, and don't let the nose get too low.

This method can also be adopted for aircraft that don't have enough elevator authority to do a turning stall.

If you're doing this in a power plane (rather than a glider), you'll probably wind up adding power in the recovery.

A stall occurs based on angle of attack, not speed. If the plane tends to nose over near stall speed, the angle of attack may not increase enough for a full stall, even though the plane is losing altitude. If you want to perform a low speed stall in the plane, keep pulling the stick back to maintain altitude or climb slightly as the power is eased off. Use the rudder to keep the wings level to reduce the likelihood of a spin.

  • That's exactly what I did. Maintaining altitude by pulling back more and more until there was no more pitch change (yoke full back). In a C172 the nose would've dropped but the C182 just started sinking, nose-high with yoke full back. – Philippe Leybaert Dec 18 '13 at 17:24
  • Interesting! I guess you could throw some weight in back (within CG limits, of course), or use a little power. – xpda Dec 18 '13 at 17:31
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    Doesn't matter how far back you've got the yoke. As xpda said, it's the angle of attack that controls a stall. In this aircraft, you ran out of elevator control before you ran out of angle of attack. You can make it stall by entering the stall a bit quicker, while you still have more ability for your elevator to increase the angle of attack. The C172 would do this as well. If you want to make the 182 break into a stall, do that again, but while you're fluttering, goose the power just a little bit to allow the elevator to increase the AoA. It'll stall. – Shawn Jan 9 '14 at 15:52
  • @Shawn: If you run out of elevator authority, the nose pitches down and the aircraft starts to descend. Which is (unless I am misunderstanding the description) contrary to the question which says “started to sink slowly with a nose-high attitude”, i.e. elevator needed enough authority to keep the nose up. – Jan Hudec May 24 '15 at 16:13
  • please don't use the rudder to keep the wings level. use the rudder to stay coordinated – rbp Aug 5 '15 at 18:05

There are some very good answers here, I enjoyed reading this post.

I would just like to add in a lot of aircraft, if you are aggressive on the rudder (in order to keep in balance at all costs, i.e. every time a wing moves slightly down you step on the sky), it is very difficult to enter a spin. The opposite is also true, if you are flying along in mushing flight and give the rudder a good kick a spin is often the result.

Different aircraft will handle differently in this mode, in some like the 182 it will be relatively easy to stay there, others could end up in a spin if the smallest of mistakes were made.

Alan Bramson used to call the aeroplane a "tin parachute" when in this mode and I believe in the olden days it was used to descend rapidly through holes in clouds (!) without building up too much speed. Although its not really a parachute because if you hit the ground in this mode the sink rate would usually be so high (in excess of 500 feet per minute), the ground would obliterate you.

To fully answer the other half of this question I think its most probably CG related and that being a new aircraft its easier than normal to keep in balance being very clean etc.

  • 1
    I assume that 500 feet per minute is a typo? The landing gear on most aircraft can survive a 1000 feet per minute drop on the runway :-) – Philippe Leybaert Aug 5 '15 at 22:52
  • I'm not sure actually. It was a figure I plucked out of my head. 500 feet per minute is 8.3 feet per second. I wouldn't like to try it - that is get a proper 500 feet per minute descent going and fly into the ground even if nose up. The BRS parachute system fitted to the Cirrus descends between 680 and 1500 feet per minute and the aircraft is usually wrecked. So the next time I'm flying at night and the engine fails I don't think I would go into tin parachute mode even if my descent rate was 500 feet per minute ( I would think in most types it would be a lot more than that). Regards Phil – Philip Johnson Aug 6 '15 at 7:49
  • Airliners need to be certified to survive a 600 fpm drop on the runway without any damage. They can usually withstand more than that. But as you said, going down in "tin parachute" mode will be in the order of a few thousand feet per minute. – Philippe Leybaert Aug 6 '15 at 14:49

My last flight involved some stall training in a PiperSport LSA, and it actually did take considerable conscious input to make the plane move past that "mushy" stage and depart completely (it would nose down quite handily when you did though).

I concur with other answers; there is a difference between a "stall" (exceeding critical angle of attack and thus losing lift and/or full attitude control) and a "departure" (losing most or all attitude control). If pulling back on the stick or yoke won't continue to pitch the nose up, you've stalled, but you haven't departed completely until you can't push the nose back down (or it noses down even with full nose-up elevator applied).

Many small planes with "normal" or "utility" category ratings (or "limited" light-sports) are designed with a large amount of "departure resistance"; their aerodynamic design and mass distribution makes it hard to fully depart the aircraft and enter a nose-down stall (or a spin, spiral dive etc). This also makes intentional maneuvering near the edges of the flight envelope more difficult, as the plane will want to settle back into a stable configuration rather than let the pilot potentially push further into departure.

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