Diana
Final Approach
I’m having a discussion with someone on altitude loss in spins. How much altitude do you all lose per turn in the different airplanes that you fly in a standard, run of the mill, upright spin?
Diana said:I’m having a discussion with someone on altitude loss in spins. How much altitude do you all lose per turn in the different airplanes that you fly in a standard, run of the mill, upright spin?
With two up and my Mooney checkout guy in the right seat, lost about 1000 per turn. Mooneys stay upright if you are vefy definite about letting elevator out PRIOR to opposite rudder- otherwise "over you go...." as in inverted. These are not logged for obvious reasons.Ed Guthrie said:From the '77 Mooney M20J POH:
WARNING
Up to 2000 feet of altitude may be lost in a one-turn spin and recovery; therefore stalls at low altitude are extremely critical.
"Run of the mill, upright spin?" Doubtful.
Ed Guthrie said:From the '77 Mooney M20J POH:
WARNING
Up to 2000 feet of altitude may be lost in a one-turn spin and recovery; therefore stalls at low altitude are extremely critical.
It is because Al Mooney was a little crazy. Really. ~1 M square wetted profile, Laminar flow wings that break all at the same time (he had to washout the AOA out to the tips with wing twist until 1968 when they discovered stall fences) for most efficient production of lift, very tapered wing approximating the Ellipitcal planform, All flying tail.Diana said:Wow. Why is that?
Thanks for the explanation Bruce. So, what are the advantages of the Mooney wing then? Faster? Better climb?bbchien said:It is because Al Mooney was a little crazy. Really. ~1 M square wetted profile, Laminar flow wings that break all at the same time (he had to washout the AOA out to the tips with wing twist until 1968 when they discovered stall fences) for most efficient production of lift, very tapered wing approximating the Ellipitcal planform, All flying tail.
Diana said:Thanks for the explanation Bruce. So, what are the advantages of the Mooney wing then? Faster? Better climb?
Ditto the Pitts and the Extra.lancefisher said:I think that WRT a one turn spin, a lot depends on the entry. Few if any planes become stable after only one turn. By the time you get to three or more things should be pretty consistent. I've had some spins in the Porterfield that lost well over 1000 ft in the first turn and some that dropped less than 500-600. I also suspect that the altitude loss depends a lot on wing loading and CG location. With the flatter attitude and higher rotation rate of an aft CG I'd expect the altitude loss to be reduced.
Gosh, I didn't realize that. No wonder you Mooney guys love your Mooneys!Ed Guthrie said:Aerodynamic efficiency (faster, better climb, and falls like a rock). Mooney aircraft are pretty much the fastest production aircraft on a kts/hp basis. As an example, a four seat, '77 Mooney M20J produces ~160 kts on 200 hp while a four seat, Beechcraft V35B of the same era produces the same speed on 285 hp.
Chip, how much do you lose in your Citabria?gibbons said:Ditto the Pitts and the Extra.
I couldn't really say. I've only spun it a few times (less than a dozen) and never more than a three turn spin. I would guess it would be close to 800' - 1,000' per turn. It spins well and wraps up tighter after a couple of turns than I expected.Diana said:Chip, how much do you lose in your Citabria?
Diana said:Gosh, I didn't realize that. No wonder you Mooney guys love your Mooneys!
Is there any way we can put these wings on top of an airplane, make it a high wing airplane and therefore make it the perfect airplane?bbchien said:It is because Al Mooney was a little crazy. Really. ~1 M square wetted profile, Laminar flow wings that break all at the same time (he had to washout the AOA out to the tips with wing twist until 1968 when they discovered stall fences) for most efficient production of lift, very tapered wing approximating the Ellipitcal planform, All flying tail.
Haha, but then you would have to climb a ladder to check you fuel.Diana said:Is there any way we can put these wings on top of an airplane, make it a high wing airplane and therefore make it the perfect airplane?
Rudy said:Haha, but then you would have to climb a ladder to check you fuel.
It is an extra risk and me being accident prone i prefer not to take it. hahaha
lancefisher said:Ed's stretching it a little.
I think the book is stretching it a bit. My 78 M20J sure wouldn't do that.Ed Guthrie said:From the '77 M20J POH: 75% power, 6000', standard conditions, the book shows 171 kts TAS.
Ken Ibold said:I think the book is stretching it a bit. My 78 M20J sure wouldn't do that.
Diana said:Is there any way we can put these wings on top of an airplane, make it a high wing airplane and therefore make it the perfect airplane?
LOL! I noticed that about you Mooney guys. At least I know how much altitude a Mooney loses in a spin. I'm still not quite sure how fast they go, however.Michael said:Sorry Diana, looks like your thread got taken over, But it just goes to show you that any topic can be converted to a mooney topic rather easily.
Ken Ibold said:I think the book is stretching it a bit. My 78 M20J sure wouldn't do that.
Ken Ibold said:I think the book is stretching it a bit. My 78 M20J sure wouldn't do that.
Ed Guthrie said:That's okay, the V35B book is stretching it a bit, too.
Honestly, I have no accurate feedback to supply right now. I'll go check tomorrow.Diana said:Now, if Ken would just tell me how much altitude he loses in his Citabria in a spin...............
Diana said:Oh gosh, this is getting to be fun. I don't remember a Mooney vs Bo thread before.
Hey, how much altitude does the Bonanza lose in a spin?
OK.Ken Ibold said:Honestly, I have no accurate feedback to supply right now. I'll go check tomorrow.
How many turns are you counting? The first two will lose more altitude than the next 5 or 6 because the rotation rate increases once you're past the incipient phase.Diana said:He did 20 turns and recovered within 4000' and that included his dive to restart the engine. His spin looked pretty flat in his video, but he said it was normal for a Robin.
It made me wonder if I was doing something wrong.
From 2 to 5 turns. I'll have to go back up and count again. That one strange spin I only lost 1500' with over 6 turns and I had someone counting the turns from down on the ground and called out altitudes beginning and ending. It was the one that wrapped up very fast and tight.Ken Ibold said:How many turns are you counting? The first two will lose more altitude than the next 5 or 6 because the rotation rate increases once you're past the incipient phase.
Skyport said:The eye-popping Mooney number of 2000' was, no doubt, written by an attorney concerned about liability.
Skyport said:My GCAA looses 300-500' in each turn,
The actual altitude loss per turn in most GA aircraft is similar in my experience, rising to the 500-700' range with higher perf, and slower rotating, aircraft. One huge difference with spinning in high perf, and cleaner, aircraft is the altitude loss during the recovery.
For the record, the plan was to terminate the cross-control stall demo at the first sign of either stall or loss of aileron control (i.e. stall warning horn, stall buffer, or aileron controls hit the stops). The two demonstrations that went further than I would have preferred proved that the aileron stops, stall buffet, stall horn, and stall break can be hit simultaneously without any extraordinary effort. Both times that happened we had an e-ticket ride. The first time it happened I thought I'd been a bit rough on the controls, but the second time confirmed to me that the cross-control stall demonstration simply wasn't a good idea even if the plan was to not actually stall the aircraft.Skyport said:Ed-
While I must admit that I've never spun a Mooney, nor is it the type of aircraft I would choose to do a cross-control stall demo in,
Pretty much you just described the first 1/2-3/4 turn in a Mooney. All I can tell you is that the Mooney spin entry is not what you might expect after spinning a C152, C172, or even a Citabria (been there in all of those). The Mooney aircraft rather abruptly rolls inverted as one wing literally falls out from under you--that wing is indeed rather sharply stalled. FWIW, the CFI I mentioned previously told me that he had decided to watch the altimeter to note how much altitude I lost during a stall recovery if one occurred. He told me the altimeter was an absolute, complete blur. I have watched a C172 altimeter during spins and it was never all that exciting.I have spun other aircraft that went inverted in the incipient phase and I find it difficult to see how 2000' could be lost in one turn. To do so would require that the aircraft be deeply into the stall and almost in free fall with only a modicum of lift on one wing providing a rotational force.
Yup. But the really in the know old Mooney guys know to teach it to those capable of learning from it. My guy was (when he was wearing his other hat) a DPE. He advised me of this, I agreed to this, and we did not log it. He had done this in the four digit numbers of times, as he was one of the original Factory Test Pilots. Jeepers!Skyport said:FYI-
One VERY important thing missing from this discussion of Mooney spins is that SPINS ARE PROHIBITED in all models........................anyone spinning a Mooney has became an Experimental Test Pilot.
Tom-