facthunter Posted January 18 Posted January 18 (edited) RAAus don't permit teaching spiral dives and recovery. In a docile plane like a Gazelle dangerous loads and speeds can happen in seconds. However "SPIN OR SPIRAL" is the first IDENTIFY decision in recovery from either. This results in a serious deficiency in Basic training. A similar situation exists with LOW flying Training. NONE permitted unless you are mustering. You can't land Take off or do a go around with out low flying or survey a place for a precautionary landing. Nev Edited January 18 by facthunter 1 1 1
Markdun Posted January 19 Posted January 19 17 hours ago, Thruster88 said: On 16/1/2024 at 8:15 AM, RocketShip said: I don't see runway elevator trim driving a tecnam or any LSA into the ground. Much bigger aircraft yes it has happened. The Tecnam with a full flying elevator and small servo trim does not require huge effort to over-ride the trim that’s for sure. Pure speculation is the possibility that on turning final (and assuming you are at an excessive low speed like 50-55kias as if you were doing a crazy short field landing, with 2 ppl aboard), with your eyes out of the cockpit checking the runway and for other aircraft, then a runaway or inadvertant trim up will still produce an up elevator force on the control stick. If you’ve already stabilised your speed on downwind and base legs I would postulate that it’s possible a pilot would allow (maybe without being even aware of it) the stick to move back to maintain the previous pressure on the stick when the speed was previously stabilised; & in the few seconds to work out what’s going on with a check on the ASI & horizon the aircraft has begun a stall/ dropped a wing in an incipient spin. Pure speculation on my part. 1 1 1
danny_galaga Posted January 19 Posted January 19 3 hours ago, turboplanner said: Not in RA Well we did them. Spins aren't allowed in ra Aus. I don't think they prohibit spiral dives. 2
red750 Posted January 19 Posted January 19 Photo of a P92 on Facebook, with the comment "That looks like a Cessna 150 with an eating disorder!" 1
facthunter Posted January 19 Posted January 19 Check it Out. Specifically prohibited. The aircraft aren't suited generally. Vne too low. Speed build up in spirals can be very rapid. A spin is at constant SLOW airspeed. Never builds up unless it installs and you don't do the best recovery. Nev 2
BrendAn Posted January 19 Posted January 19 19 minutes ago, danny_galaga said: 18.3 Might pay you to read a bit further. That is the syllabus for weight shift. Trikes not 3 axis 1 3
jackc Posted January 19 Posted January 19 2 hours ago, mkennard said: My Jab has electric flaps. Yes and I don’t like the way I need to use them. Reach across with left hand and use switch by holding with finger, at the same time watching that little indicator cable on the extreme right side of cabin. Simply should be a rotary multi position switch on instrument panel to select desired flap setting. Select, forget and continue flying plane. Set switch as desired, when needed. iF my aircraft was 19 rego, I would fix it in a heartbeat. 2 1
facthunter Posted January 19 Posted January 19 (edited) It's certainly dangerous in some RAAus planes like the Gazelle where the wing has come off and re the low level stuff thrashed this out with Mick Poole exhaustively And got nowhere even though I have low level training in Commercial Jets and TAUGHT aerobatics and low level in GA ALL documented.. I did demonstrate recovery and briefed it thoroughly as to the risks involved with a few trusted students. The picture I've painted is from personal experience, not hearsay as an RAAus Instructor.. I haven't been able to expand what you posted. Nev Edited January 19 by facthunter 3
danny_galaga Posted January 19 Posted January 19 29 minutes ago, facthunter said: It's certainly dangerous in some RAAus planes like the Gazelle where the wing has come off and re the low level stuff thrashed this out with Mick Poole exhaustively And got nowhere even though I have low level training in Commercial Jets and TAUGHT aerobatics and low level in GA ALL documented.. I did demonstrate recovery and briefed it thoroughly as to the risks involved with a few trusted students. The picture I've painted is from personal experience, not hearsay as an RAAus Instructor.. I haven't been able to expand what you posted. Nev Could be because I was converting from GA he demonstrated it? I didn't find it very alarming as others have alluded to. Stalls were scarier. Perhaps he was just showing me the very first signs? I remember the main thing to watch is that a spiral dive has increasing speed whereas a spin (I've never been in a spin, just from what I've been taught) has a decreased or negligible airspeed. Dive- close throttle, level wings, gently pull back. spin- open throttle, level wings, opposite rudder, release pressure on stick etc 1
peterg Posted January 19 Posted January 19 3 hours ago, skippydiesel said: My apologies if I am repeating another earlier opinion: Why on earth do small aircraft (like Tecnam) have electric trim? AND electric flaps. This is an unnecessary complication/potential failure point in what should be a simple (KISS) aircraft. Electrically operated flaps & trim take very little space in an already compact environment and likely reduce empty weight in most installations compared to the manual version - a couple of things designers are acutely aware of when designing aircraft with weight limitations 1 1 2
danny_galaga Posted January 19 Posted January 19 (edited) 1 hour ago, peterg said: Electrically operated flaps & trim take very little space in an already compact environment and likely reduce empty weight in most installations compared to the manual version - a couple of things designers are acutely aware of when designing aircraft with weight limitations Dunno. The Tecnam Golf has a roughly similar layout to the PA 28 warrior. As far as I could tell, the warrior basically had a 'handbrake' bolted directly to the rod connecting the two flaps. Or looking at my own plane, the 'handbrake' pulls on a couple of bellcranks going to each flap. I can't see how using an electric motor, with a gearbox plus the wiring could be lighter. Of course maybe it's easier because of dihedral on the golf - just use two motors. But that sounds like even more weight. Thinking on this accident, again this is on the golf, I haven't flown the p92, when you close the throttle to descend before turning base, you put in full up trim to slow to descent speed. So if the trim 'ran away' it can only go pretty much one direction which is in the direction of higher speed/over shooting. On reflection doesn't seem like a runaway trim would cause a spin in this situation. Am i thinking about this correctly? Edited January 19 by danny_galaga 1
facthunter Posted January 19 Posted January 19 SPIRAL is about right. Spin Lets just say PLANES can be a lot different. Know the technique for the plane you're flying. Your spin recovery is way off so attend to that. The TWO electric flap motors?? What about assymmetry?? It's lethal. and never brought up with U/ls The thing with the P92 is the high drag with lowering flap and how quickly the speed can drop off if you don't watch it and lower the nose or put on a bit of power. ALSO you trim after you get the required pitch and speed to RELIEVE control forces. You don't fly on trim. If you're a bit fast the force required to lower the flap should alert you to the Fact. (Feel). You can also dump flap on the ground more quickly if that helps braking. Weight on wheels. Nev
danny_galaga Posted January 19 Posted January 19 32 minutes ago, facthunter said: SPIRAL is about right. Spin Lets just say PLANES can be a lot different. Know the technique for the plane you're flying. Your spin recovery is way off so attend to that. The TWO electric flap motors?? What about assymmetry?? It's lethal. and never brought up with U/ls The thing with the P92 is the high drag with lowering flap and how quickly the speed can drop off if you don't watch it and lower the nose or put on a bit of power. ALSO you trim after you get the required pitch and speed to RELIEVE control forces. You don't fly on trim. If you're a bit fast the force required to lower the flap should alert you to the Fact. (Feel). You can also dump flap on the ground more quickly if that helps braking. Weight on wheels. Nev Right you are. I might have been thinking of a flat spin for power. Bear in mind I've never done one. I've thought about going up in a glider to do some spin training. Tonight I'll watch some training videos on spins to get my head right. About what I said about trim. I was probably being a bit perfunctory there about the procedure with the golf. I'm translating my muscle memory into words! First thing is close the throttle to idle, and the nose will drop. As you do this hold the trim up button. It takes a number of seconds so you should do it pretty much straight after shutting the throttle. Personally the main reason I don't like electric trim is this adjusting via 'timing' rather than by position. Especially planes like mine or the Savage Cub, you just push the trim lever instantly to the approximate position, then of course fine tune it by feel. And now you mention it, yes two flap motors would not be a good idea. Which still leads some of us to ask- why electric? My theory is it's easier to bolt an electric motor where you need and run electrical cables however you like, than to maybe have to design around some awkward geometry for control cables etc. Mind you, again looking at my plane, the trim is push/pull via Bowden cables so geometry isn't critical. 1
Markdun Posted January 19 Posted January 19 I’ve tried to ‘fly on trim’ in my Cygnet to see if I could fly it that way if there was a failed elevator (broken cable) event. This is a mech trim to a small servo tab on the elevator controlled by a Bowden cable. It’s possible; but every trim adjustment input results in 3 or 4 slow sigmoidal pitch oscillations. The Cygnet is pitch, roll & yaw stable (if you let the controls go it will level off and fly straight…. maybe a little left yaw). My conclusion is that it would be possible to achieve a landing but you would need a long final leg to become stabilised and 1000m of non-undulating runway. Danny, my experience is in a Bravo and that plane’s trim still has maybe 20% more up at 65kias & 16 degrees of flaps, (which is what I use….full flaps scares me a bit), zero stick force, engine at idle, 2 ppl. I did spin training in a Blanik and that plane’s spin has a very nose down attitude and with increasing speed…. a challenge to do the 5 turns before Vne and then recover. And you would never recover by ‘level the wings’ with aileron (which would condemn you further, perhaps to an inverted spin). Recover by full opposite rudder (to level wings via secondary effect of rudder) & zero elevator, check down elevator only if necessary (which never was the case as youre pretty close to Vne). And for an incipient spin (one side wing drop near stall) recovery you just pick up that wing with the rudder & increase speed a tad (this is something we practiced a lot fiddling around at cloud base in a good thermal). With an engine I have no experience, but in the absence of advice in a flight manual I think the recommendation is to close the throttle. 1
danny_galaga Posted January 19 Posted January 19 Yeah my only experience with electric trim is the golf, which is generally full up. For me I need it one led down from that. That's not much more up.
facthunter Posted January 19 Posted January 19 (edited) IF you are spinning you WILL NOT Increase speed. It will stabilise somewhere near stall speed depending on where your Pitot is located. FLAT spins are the hardest to recover from.. You will only get into an inverted spin by putting the stick well forward. There's a lot to know about spinning and you are NOT there. and I'm not going into it here in detail. I'll respond to specific questions on Principles. Spins are called AUTOROTATION. What the plane is doing is not directly what the controls position would normally have you doing. Nev Edited January 19 by facthunter 1
derekliston Posted January 19 Posted January 19 Back when I learned to fly in the UK spin recovery was a part of the PPL test although. I believe it no longer is a requirement? That was circa 1970. Personally I believe that every pilot should experience a spin and recovery even if only demonstrated by an instructor in a suitable airframe, Decathlon for example! 2 1
danny_galaga Posted January 19 Posted January 19 56 minutes ago, facthunter said: IF you are spinning you WILL NOT Increase speed. It will stabilise somewhere near stall speed depending on where your Pitot is located. FLAT spins are the hardest to recover from.. You will only get into an inverted spin by putting the stick well forward. There's a lot to know about spinning and you are NOT there. and I'm not going into it here in detail. I'll respond to specific questions on Principles. Spins are called AUTOROTATION. What the plane is doing is not directly what the controls position would normally have you doing. Nev Understand all that, and that it is not wise to be giving lessons on spins on a forum. You may have misunderstood what I was asking before. Markdun has mostly answered it. I was basically asking if a runaway trim could even cause a stall or spin when it is already all, or almost all UP. Before you even turn to base. In a sense, the only way is DOWN from there. And of course I only have my experience with the golf as a guide. The P92 may need hardly any up trim for all I know...
BLA82 Posted January 19 Posted January 19 Can I please ask that all the speculation be raised in another chat. This seems to have gone off topic. People have lost a great mate and I'm sure friends and family don't need to see the what ifs. Just my 2 cents. Ben 2 1
danny_galaga Posted January 19 Posted January 19 Sorry, you are of course right. I'm heading to Boonah tomorrow.
Methusala Posted January 19 Posted January 19 1 hour ago, facthunter said: IF you are spinning you WILL NOT Increase speed. It maybe that Mark was referring to airspeed climbing quickly following recovery from spinning. Blaniks spin very nose down perhaps 70deg?
facthunter Posted January 19 Posted January 19 Marks info is not correct, either so I don't know which part of it has answered your question. VNE is never a problem in a spin. If it was in the recovery your technique is way down. The full opposite rudder is to stop the turn (YAW) Often the horizontal stab and elevator will blanket the rudder. You can see this likelihood in some designs. Mass in the extremes of the fuselage predisposes to a flat spin which is the most difficult to unstall from. . The discussion seems to mainly address trim and it may be the cause or contribute to it.. When on base you aren't very high and you wouldn't have the height to recover from either. IF your pitch attitude was steeply toward the ground you could NOT recover either at that height. Nev
facthunter Posted January 19 Posted January 19 I just feel I have to sort out a few misconceptions. Two well experienced pilot s are now not with us and some would wonder if they can't cover it, how would I go?. I have never intended any disrespect to the pilots and don't like speculation either. My usual comment is along the lines of "you weren't there, were you" ? Nev 2
Area-51 Posted January 19 Posted January 19 No amount of talking, reading, or flying in Sims is going to prepare any individual for their first real spin in a real aircraft. Chances are high that if they have never experienced a spin and end up in one on their own then they will not be arriving home for tea that evening. Probably the only way the inexperienced pilot will know they are in a spin for the first time is the following, feeling mentally totally overwhelmed, situationally totally disorientated, physically unable to respond (these aspects diminish after the third or fourth entry and recovery of the manoeuvre). If they are in an aircraft with an instructor for the specific purpose of experiencing spins the inexperienced pilot will likely be arriving home for tea. You cannot learn how to negate a spin recovery by just reading a book. It would be foolish ignorant and arrogant for anyone to believe they are prepared enough by just doing so. Invest in yourself. Find a suitable instructor and go do the training. 2
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