How safe is stall practice in a non spin certified aircraft?
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Vabsie, crashes of light aircraft are very rare and the few statistics that might be gleaned from them will not tell you all that much about the safety of a particular airframe. So just because you happened to stumble upon a story about an R2120 crash doesn't mean they're less safe than a C152.
in fact, once you start reading accident reports a bit more you will quickly realize that the biggest cause of light aircraft crashes is actually pilot error. Continued flight into IMC, fuel exhaustion or fuel starvation, flight outside the structural limits of the aircraft or gross mishandling of the aircraft at low level. Not by engine or airframe failures.
Personally I like the R2160 a lot more than the C152. It feels much roomier with a much better view. And of course the one I fly has the ability to be turned upside down...
But anyway, you need to realise that at your stage of training it's best to stick to one airframe. Whether that's a C152 or an R2120 doesn't really matter. They're both perfectly good trainers. Once you've got your PPL and a few hours experience, you will want to get checked out on several (maybe all) types that the club operates. This gives you the ability to pick the aircraft type that's best for the mission that you're going to fly.
So pick an aircraft type that you find comfortable to fly in and that has good availability. Finish your training on that type. Other types will come in due course.
in fact, once you start reading accident reports a bit more you will quickly realize that the biggest cause of light aircraft crashes is actually pilot error. Continued flight into IMC, fuel exhaustion or fuel starvation, flight outside the structural limits of the aircraft or gross mishandling of the aircraft at low level. Not by engine or airframe failures.
Personally I like the R2160 a lot more than the C152. It feels much roomier with a much better view. And of course the one I fly has the ability to be turned upside down...
But anyway, you need to realise that at your stage of training it's best to stick to one airframe. Whether that's a C152 or an R2120 doesn't really matter. They're both perfectly good trainers. Once you've got your PPL and a few hours experience, you will want to get checked out on several (maybe all) types that the club operates. This gives you the ability to pick the aircraft type that's best for the mission that you're going to fly.
So pick an aircraft type that you find comfortable to fly in and that has good availability. Finish your training on that type. Other types will come in due course.
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If I remember correctly, that r2120 that crashed was the result of the pilot trying to out climb rising terrain.
I wouldnt say the robin is any more or less safe than anything else out there, the r2160 has pretty good performance (best i have had is 1700fpm on a high pressure winter morning with only me and 2 hours fuel) and visibility is excellent which is definitely a good safety feature.
Just gotta remember the plane is only as safe as the pilot flying it
I wouldnt say the robin is any more or less safe than anything else out there, the r2160 has pretty good performance (best i have had is 1700fpm on a high pressure winter morning with only me and 2 hours fuel) and visibility is excellent which is definitely a good safety feature.
Just gotta remember the plane is only as safe as the pilot flying it
I have lots of thoughts on this thread, and quite a few disagreements with some of the previous posters.
Firstly - a stall in itself, in a certified aeroplane, is NOT dangerous. At a safe height it is a perfectly reasonable thing to practice, and I believe that as well as stall avoidance and slow flight, all pilots should practice a proper stall once in a while. Very few certified aeroplanes will show any tendency to spin from a sensibly conducted stall, and pretty much all of those will recover from the incipient spin if you simply put all of the controls in the middle and close/keep closed the throttle.
What will kill you is not the stall and stall recovery, it is the height loss if you stall close to the ground. For this reason, it is generally sensible not to practice stalls anywhere below 1500ft agl, or 3,000ft agl if being particularly cautious for any reason. It is however sensible to practice stalls in the circuit - by which I mean visualise an imaginary runway at, say, 3,000ft and practice approaching the stall and recovering from the finals turn, approach, go-around, and climb-out (the last two being statistically the most dangerous, not the finals turn - although that certainly is significant).
A sharp pilot, practicing a stall and recovery deliberately is likely to lose 50-100ft in the recovery, whilst an average pilot recovering from an inadvertent stall will probably lose 200-300ft. Given that, and a bit of safety margin, it's below 500ft that stalls are truly dangerous.
When we certify a new aeroplane type, we will look at a range of stall scenarios - flap settings, power, bank angle, deceleration rates - going rather beyond what should be flown during PPL training. If the aeroplane shows any tendency to spin, that must be sorted out before the aeroplane is certified.
When we certify a non-aerobatic aeroplane type, we still spin it, still confirm that it will recover within a turn, still evaluate mishandled recoveries, and still confirm that it has no unrecoverable spin mode. What we don't do is go beyond 2 turns - rather more is required for an aerobatic aeroplane.
In the UK for the last 12 years, this has also applied to microlight aeroplanes - although that is not the practice in most countries. However, the large powerful cruciform tails on most microlights together with existing requirements for good low speed handling, tend to assure very good stalling characteristics anyhow. The best spin recovery for most microlights however is to close the throttle and put the stick and rudder in the middle - NOT the conventional light aeroplane opposite rudder recovery (there are numerous reports and research papers out there proving this, it's not just my opinion, although I did write some of the reports.)
So, in my opinion, whilst the first and most important part of stall training is avoidance, this is certainly followed by recovery. Practicing stalling is essential for a safe pilot, and at a reasonable height, is a perfectly safe and sensible thing to do. The risk of a spin is tiny, and of an unrecoverable spin far tinier still.
Further thoughts: train now on the nearest possible aeroplane to what you plan on flying after you have your licence. There's nothing wrong with either the C152 or the Robin, nor particularly with switching types in the middle of training - just don't switch too often until you're rather more experienced (and licenced). Personally I'd stick with the Robin, but purely because I think that they're more enjoyable to fly.
G
Firstly - a stall in itself, in a certified aeroplane, is NOT dangerous. At a safe height it is a perfectly reasonable thing to practice, and I believe that as well as stall avoidance and slow flight, all pilots should practice a proper stall once in a while. Very few certified aeroplanes will show any tendency to spin from a sensibly conducted stall, and pretty much all of those will recover from the incipient spin if you simply put all of the controls in the middle and close/keep closed the throttle.
What will kill you is not the stall and stall recovery, it is the height loss if you stall close to the ground. For this reason, it is generally sensible not to practice stalls anywhere below 1500ft agl, or 3,000ft agl if being particularly cautious for any reason. It is however sensible to practice stalls in the circuit - by which I mean visualise an imaginary runway at, say, 3,000ft and practice approaching the stall and recovering from the finals turn, approach, go-around, and climb-out (the last two being statistically the most dangerous, not the finals turn - although that certainly is significant).
A sharp pilot, practicing a stall and recovery deliberately is likely to lose 50-100ft in the recovery, whilst an average pilot recovering from an inadvertent stall will probably lose 200-300ft. Given that, and a bit of safety margin, it's below 500ft that stalls are truly dangerous.
When we certify a new aeroplane type, we will look at a range of stall scenarios - flap settings, power, bank angle, deceleration rates - going rather beyond what should be flown during PPL training. If the aeroplane shows any tendency to spin, that must be sorted out before the aeroplane is certified.
When we certify a non-aerobatic aeroplane type, we still spin it, still confirm that it will recover within a turn, still evaluate mishandled recoveries, and still confirm that it has no unrecoverable spin mode. What we don't do is go beyond 2 turns - rather more is required for an aerobatic aeroplane.
In the UK for the last 12 years, this has also applied to microlight aeroplanes - although that is not the practice in most countries. However, the large powerful cruciform tails on most microlights together with existing requirements for good low speed handling, tend to assure very good stalling characteristics anyhow. The best spin recovery for most microlights however is to close the throttle and put the stick and rudder in the middle - NOT the conventional light aeroplane opposite rudder recovery (there are numerous reports and research papers out there proving this, it's not just my opinion, although I did write some of the reports.)
So, in my opinion, whilst the first and most important part of stall training is avoidance, this is certainly followed by recovery. Practicing stalling is essential for a safe pilot, and at a reasonable height, is a perfectly safe and sensible thing to do. The risk of a spin is tiny, and of an unrecoverable spin far tinier still.
Further thoughts: train now on the nearest possible aeroplane to what you plan on flying after you have your licence. There's nothing wrong with either the C152 or the Robin, nor particularly with switching types in the middle of training - just don't switch too often until you're rather more experienced (and licenced). Personally I'd stick with the Robin, but purely because I think that they're more enjoyable to fly.
G
Moderator
Ideally, good initial training will focus first, but by no means only, on stall and spin avoidance. With good pilot skill (though still in the training phase) stall recovery should be instinctive. A stall which threatens flight safety is going to happen when you're trying to do/not do something else in flight, and you're distracted. Recovery must be instinctive. Also, remind yourself, that it is perfectly acceptable for a well controlled stall to go unrecovered on every flight - the flare and touchdown.
It is possible in any light type (certainly some more easily than others) to aggravate a simple stall into something which turns into a spin. This is why you'll be taught to recognize and recover a stall promptly, but effectively, the first time. A buggered up stall recovery is taking you much closer to a spin.
The spin in a certified light aircraft, in and of itself, is not a serious problem, as long as you are going to correctly recover it, with lots of space around you, and without exceeding limitations. Do not go spinning without proper training and supervision, but certainly do go spinning. I am not an expert on spinning, as it is a very complex subject. But, I have spun about a dozen aircraft types during certification flight testing, and have experienced very different characterisitcs, and recovery conditions.
(Nearly) all ('cause I know nothing about Cirrus) certified aircraft are recoverable from a spin, it's a design requirement. Those which are not spin approved are so either because the manufacturer did not wish to have spin approval, or more commonly, because though recoverable, you get very close to limitations doing it. Add to that, that the recovery technique may be variable, based on configuration, and the techniques or cautions too variable to try to describe to the pilot in the flight manual.
My recent testing experience (on test flight permits) includes many stalls in two Piper Navajos, where, while trying to accomplish minimum altitude loss, it was easy to get a secondary stall, and have a rather messy secondary recovery. Certainly a spin could have been obtained doing that, if one was careless. In January, I did more than a dozen spins in a modified Cessna Grand Caravan. Though the handling of this larger aircraft in the spin is magnificent, it would be easy to exceed limitations during the recovery, without great caution. I installed a G meter, and was happy I did, as the recovery for a forward C of G gross weight spin required a 2.8G pull, at Vne. There's not much room to get that recovery wrong! The aft C of G handling and recovery, though also fine, was very different.
There's a video clip here:
It is possible in any light type (certainly some more easily than others) to aggravate a simple stall into something which turns into a spin. This is why you'll be taught to recognize and recover a stall promptly, but effectively, the first time. A buggered up stall recovery is taking you much closer to a spin.
The spin in a certified light aircraft, in and of itself, is not a serious problem, as long as you are going to correctly recover it, with lots of space around you, and without exceeding limitations. Do not go spinning without proper training and supervision, but certainly do go spinning. I am not an expert on spinning, as it is a very complex subject. But, I have spun about a dozen aircraft types during certification flight testing, and have experienced very different characterisitcs, and recovery conditions.
(Nearly) all ('cause I know nothing about Cirrus) certified aircraft are recoverable from a spin, it's a design requirement. Those which are not spin approved are so either because the manufacturer did not wish to have spin approval, or more commonly, because though recoverable, you get very close to limitations doing it. Add to that, that the recovery technique may be variable, based on configuration, and the techniques or cautions too variable to try to describe to the pilot in the flight manual.
My recent testing experience (on test flight permits) includes many stalls in two Piper Navajos, where, while trying to accomplish minimum altitude loss, it was easy to get a secondary stall, and have a rather messy secondary recovery. Certainly a spin could have been obtained doing that, if one was careless. In January, I did more than a dozen spins in a modified Cessna Grand Caravan. Though the handling of this larger aircraft in the spin is magnificent, it would be easy to exceed limitations during the recovery, without great caution. I installed a G meter, and was happy I did, as the recovery for a forward C of G gross weight spin required a 2.8G pull, at Vne. There's not much room to get that recovery wrong! The aft C of G handling and recovery, though also fine, was very different.
There's a video clip here:
[They're both the same video, I don't know why it's there twice]
As for your instructor making a remark about it being risky to spin the aircraft, perhaps your instructor is more referring to his/her comfort level, rather than the capability of the aircraft. Ask how experienced you instructor is spinning this type.
