Cessna 170 Aerobatic?

[jrenwick]

My primary training was in 1970, and I don't know if spin training was still required for a private license then, but my instructor did it. The drill was to stall the airplane, power-off and straight ahead, and just as the stall breaks, apply full rudder in one direction or the other, while holding full up elevator. Opposite aileron at the same time might be required to get a good spin entry. The airplane always spins in the direction the rudder is applied. The inside wing stalls and drops. You may roll inverted for a moment, and then you find yourself right-side-up but nose-down and rotating in the direction you're holding the rudder. Airspeed will be low and staying that way. You hold the full elevator and rudder inputs for the planned number of turns, then you recover with opposite rudder to stop the rotation, neutralize the ailerons, then nose-down elevator to regain speed, then gentle up-elevator to recover from the dive, and finally add power to finish the recovery. (This was in a C150; the prescribed order of inputs will differ slightly for different aircraft types, per the POH.)

That's a fine exercise; you learn how to recover from a spin, which might be helpful if you've entered it with enough altitude.

But the spins that kill people are seldom entered from an altitude that permits recovery. They are mainly of two varieties: turning from base leg to final, or circling to look at something on the ground (in Alaska they call that the "moose stall"). Because you're already turning, the bank angle "accelerates" the stall, meaning that you stall while you're still in the green arc. If your rudder inputs are uncoordinated at that point, you may quickly become dead.

Suppose you're turning from base to final and you see you're overshooting the runway centerline, so you step on the inside rudder to bring the nose around more quickly, but your instructor told you never to bank more than 30 degrees in the traffic pattern, so you're holding opposite aileron to keep the bank shallow, and then you're pulling back to help get around the turn. You're all set up for a spin at that point. The inside wing stalls, and you smack the ground before you have a chance to even figure out what's happened, let alone what to do about it.

Or suppose you see something really cool on the ground, like a big bull moose, and you want to make sure everyone in the airplane gets a good look at it. You're almost overhead, so you've got to bank pretty steeply to keep it visible. That gets you turning awfully fast, so you use some top rudder to stop that. The outside wing stalls, you roll inverted in that direction, and down you all go.

Or you take off, and a couple hundred feet off the ground your engine dies because you had an empty tank selected. You see only trees ahead, so you bank and wrap it around to get back to the runway, and you need some extra rudder to help get it around....

These are all ways that people get dead in airplanes, and it continues to happen. People have designed airplanes so as not to be able to spin, but that makes them not fun to fly, and people don't buy them. So as long as pilots fly, we've got to understand spins and how always to avoid getting close to entering one. Because folks, just about the only times spins are recoverable is when you've planned them!

Best Regards,

John

[N1478D]

The 170 is a VERY SAFE airplane. It will just barely kill you!

[jrenwick]

The 170 is a VERY SAFE airplane. It will just barely kill you!

I've mostly heard that said of J3s and other Cubs, with the emphasis on "barely" (as NTSB reports will confirm). Said of 170s, much as I love 'em, the operative word is "will."

[bradbrady]

John,
Your post on spins was exclent! Just the way I think! But about your comment on spinproof aircraft, I think an Ercoup in a heavy cross wind is a hoot to fly
brad

[jrenwick]

John,
Your post on spins was exclent! Just the way I think! But about your comment on spinproof aircraft, I think an Ercoup in a heavy cross wind is a hoot to fly
brad

Thanks! Did the Ercoupe have the crosswind gear option?

[KMac]

I recommend all aviators take some spin training - heck even the basic rolls and loops are great fun. I had to do spins when I trained for my private pilot and more recently, I had the opportunity to take some aerobatic lessons. They are more difficult to do correctly than you would think. Someone wrote about it previously - whoever is doing the "loop" in that 170 is really doing something like a lower case cursive L not an O.
Aerobatics are great fun, but do this training with a qualified instructor, a parachute and in an airplane that was meant to do aerobatics! Personally, I would not push my 57 year old airplane that much.
For what its worth.
Kevin

[flat country pilot]

John,

Good post.

Keep the ball centered and enough airspeed.

Bill

[jrenwick]

Thanks, Bill! I appreciate the compliments.

Reflecting on this some more, it occurs to me that many stall/spin fatal crashes occur while the pilot is flying with reference to the ground in one way or another. For me, this reinforces the importance of the ground reference maneuvers we practice for the private and commercial ratings, and the necessity of learning good coordination and airspeed control while we're doing them. Those maneuvers might actually be the best "spin training" we get.

[c170b53]

During my initial training the instructor had difficulty in demonstating the optical illusion of increased aircraft speed when in a bank with "drift. The instructor did his best but the coin didn't drop for me until I was setting up for final in a very tight (terrain) pattern. Looking at the ground, I felt as if I was going a millon miles an hour (albeit usual speed for us lycoming powered types) and that the cross wind was going to blow me way past a straight in final approach. There was an urge to pull back on power or bank harder, but I kept to my plan thinking I would just go around. I was surprised when I rolled out to see the runway where I thought it would be. I'm sure someone is thinking I should have planned my arrival differently but sometimes we are not given the choice due airspace restrictions and regulations.

[bradbrady]

John,
Your post on spins was exclent! Just the way I think! But about your comment on spinproof aircraft, I think an Ercoup in a heavy cross wind is a hoot to fly
brad

Thanks! Did the Ercoupe have the crosswind gear option?

John,
that was funny! Of course the only Ercoupe's I have ever flown were C's and CD'S converted to D's So they all had the trailing link gear, I know that you know all about! And Boing tought their early students how to land their 707's. Fred Wieck was a gienus there is no doubt! But the harder part of flying an Ercoupe, isn't the landing but the take off!!!
brad

[Indopilot]

I managed to miss the Curtiss Washington flyin back in the early 90's where after a few cans of courage and a little practice away from the field one of the local 170 owners came over the field to demonstrate his low altitude barrel roll. He managed to split S out of the manuver and kill himself on the airstrip in front of everybody. My eyewitness friend started to run to the wreckage with everyone else when he realized it was a waste of time and manpower since the guy was already dead and wasn't feeling the fire burning him anyway. Made quite an impression. Not sure how that fellow got to be 70 years old after listening to him tell about his other exploites before his grand finale . Not supposed to be any old ,Bold,Pilots. Brian

[Dave Clark]

All this talk makes me remember 30 years ago when I was a very fresh pilot. About 200 hours and some 50 hours on my 170A model. While fueling near Spokane on a cross country I walked into the fuel office to pay. Some old timer there asked "Is that NXXXX?" I said well yes it is. His next comment was "I used to own that plane. It sure loops and rolls nice!"

At that instant I knew where the slight wrinkle in the right wing came from I used to spin that 170 quite frequently just for fun but never any loops or rolls. Later I owned a few fully aerobatic airplanes to get that out of my system.

[theduckhunter]

What's safe for one pilot is not necessarily safe for another pilot. A loop and a spin can be 1 G maneuvers.

http://www.alexisparkinn.com/photogalle ... hoover.avi

Robbie Yeaman
1954 Cessna 180

[ron74887]

There is a good article in AOPA magazine this issue about how much different stalling an unloaded vs loaded airplane and how much more force is required to recover from and aft cg load. even if practicing stalls empty doesn't mean it will even come close, it's (recovery) completely different when fully loaded. Good article. Ron

[dacker]

Robbie, I believe the issue (at least for me) is about performing aerobatics in an airplane that is not certified for it, w/out a parachute, and doing a poor job while attempting it. Aerobatics when performed properly are safe, challenging and loads of fun. When performed as that yahoo did, is (like I said at the beginning of this thread) a blemish to general aviation, and if he winds up killing himself will be a black mark on the safety record of our 170s. In case anyone didn't notice he had the stall horn blaring at least twice in each loop, on pull up and in the dive portion which means he had an excessive angle of attack when he shouldn't have. Really, pretty poorly executed loops. Does he know the procedures for getting out of a spin? Does he know the procedures for getting out of a flat spin? Does he know the procedures for getting out of an inverted flat spin? These are minimum procedures one should know for aerobatics. By the way it takes more than one G to pull up and over a loop. Perhaps some aerobatic experts can chime in.
David