Concerning Vne

[flyguy]

I'm just jumping into this without much thought.

Any one with experience exceeding Vne in a Taylorcraft, or know of anyone in past history who has done it by any margin either by accident, in violent weather, during aircraft testing, messed up loop, ect.?

Any real knowledge of what comes apart first or what is most likely to fail first?

Have I seen doubled tail wires on Clipped wing T's?

DC

[Robert Lees]

Re: Concerning Vne

Well I'm sure "Clipped wing T's" come with different stress & speed criteria, so I'd be very nervous about using those criteria in other than one so designed.

I'm sure they have two tail wires for a good reason; go have a look at Pitts'; they were designed from the Taylorcraft, and some of them have two upper wires and one lower (plus a rigid brace).

I don't really mind which will fail first: I just don't want to be on board at the time.

[lfries]

Re: Concerning Vne

I doubt mine will get to Vne.

[Tom T]

Re: Concerning Vne

I took a Cessna 170 past red line, in a dive buzzing a site next to a mountain, I suggest you never exceed the red line. I learned the hard way!!!!!! As I went to pull up and turn to miss the mountain, NOTHING worked! I was in a secondary stall and the elevators, rudders and ailerons were not catching any air so it would just go strait ahead and down at the angle I had last pointed it before reaching red line. NOTHING WORKED!
About 500 feet agl and closing I Got Real Busy!
I pretty much figured I would not be home for dinner that night and then I remembered what an old time P38 pilot told about a similar situation he had in a P38. He was showing off for a Navy ship and put his P38 in an excessive dive and got into a secondary stall and as a last resort he ADDED full power and gained a slight bit of control from the elevators. I was a very lucky man to have known him because that is exactly what it did to make my recovery.Those are things that none of us are taught except the hard way. [NOT RECOMMENDED]
That P38 Pilots name was Sam Gracio, Battan death march survivor and escapee. Wrote the book; Return to Freedom.

[resojames]

Re: Concerning Vne

I used to regularly take my Clip wing to 140 MPH. Mine did have 4 tail wires as I think most clip wings have. I talked to several competitors who were competing in intermediate and told me they went to 150 to 160. Don't know if I believe them, but that is what they said it would take to get a full roll on an an up line and still have enough energy to top off the maneuver.

I took a Cessna 170 past red line, in a dive buzzing a site next to a mountain, I suggest you never exceed the red line. I learned the hard way!!!!!! As I went to pull up and turn to miss the mountain, NOTHING worked! I was in a secondary stall and the elevators, rudders and ailerons were not catching any air so it would just go strait ahead and down at the angle I had last pointed it before reaching red line. NOTHING WORKED!
About 500 feet agl and closing I Got Real Busy!
I pretty much figured I would not be home for dinner that night and then I remembered what an old time P38 pilot told about a similar situation he had in a P38. He was showing off for a Navy ship and put his P38 in an excessive dive and got into a secondary stall and as a last resort he ADDED full power and gained a slight bit of control from the elevators. I was a very lucky man to have known him because that is exactly what it did to make my recovery.Those are things that none of us are taught except the hard way. [NOT RECOMMENDED]
That P38 Pilots name was Sam Gracio, Battan death march survivor and escapee. Wrote the book; Return to Freedom.

[blakecarl]

Re: Concerning Vne

Ok, I have heard of a secondary stall being what happens after an initial stall when you begin to pitch up before gaining adequate air speed. Is that what is being referred to here?

[Larry Lyons]

Re: Concerning Vne

Sounds like hi-speed stall but was not aware you could get a lowly 172 in to that predicament. L

[resojames]

Re: Concerning Vne

I don't think it was secondary stall- you would have to get the initial stall first. A C172 would not survive a stall at 170mph. I think the structural speed ( the speed where a stall will not over stress the plane) is in the 125 MPH range.

[Tom T]

Re: Concerning Vne

Ok, I have heard of a secondary stall being what happens after an initial stall when you begin to pitch up before gaining adequate air speed. Is that what is being referred to here?

Not in my case, What happened to me was it was going to fast for the air stream to have any affect on the control surfaces. No actual stall occured, just plain going to fast. BTW it was a Cessna 170, not 172 and as memory serves me red line at 160 mph

[crispy critter]

Re: Concerning Vne

All 170's have a red line of 160mph. I have had all 3 models of the 170 up to 160mph and they handle it fine but I didn't intentionally try to pull hard on anything. Also,high speed stalls are usually caused when there is too much air across the top of the wing for the elevators to effectivly change the angle of attack unless you slow down.....the best way to do this is reduce throttle rather then add throttle. In a P38 I could see where it might give enough blast across the tail to help but I find it hard to get a 170 fast enough to have this problem and I wouldn't think the 145 Cont would give that much of an extra blast to help if you did get that fast. Not saying it's not possible but highly unlikely. I was playing around in my dad's ragwing 170 one morning doing split S's....one to the right then one to the left. I had done 3 or 4 of them and was just rolling over the top and tucking under, when I pushed the bottom to pull the vernier style throttle back the bottom stuck and would not work!!! I was already coming off my back and pointing almost straight down at full throttle, you never seen someone spin a throttle knob so fast in your life but it wasn't near fast enough. As the throttle came off I was consentrating on the most gentle recovery in history. As the nose started to lift back into the level attitude and the throttle finally came back to idle I caught my first look at the airspeed which was just passing 210mph on the way back down!!!(airspeed run out of numbers at 220mph). I have no idea how fast it got up to and honestly probably didn't have enough numbers to tell me if I had've took time to look. I honestly figured I had done stress damage to the airframe but after confessing my goof up to dad he assured me that it had been that fast before,lol......however we pulled every single panel,plate,headliner,etc and inspected every single inch of her inside and out....we also replaced the throttle cable(cracked button was the cause). There was never any problem with the recovery or the way the airplane performed,but I wasn't trying to pull out hard, I had plenty of altitude and plenty of time to take my time with the recovery.
As for a clipped t-craft, I've took one to 160mph more then once to pull off a couple of manuvers that I was later taught how to do them properly without depending on extra speed to carry me thru but by using the wing and every last bit of energy...which made it much easier to do,much easier on the airframe,much easier on the engine,and a hell of a lot easier on the pilot,lol. Amazing what you can learn from someone who really knows what they're doing.

[freightpilot27]

Re: Concerning Vne

why would anyone take a 60 year old airplane to redline? or past?

[crispy critter]

Re: Concerning Vne

why would anyone take a 60 year old airplane to redline? or past?

My excuse is youthful stupidity....and once or twice by complete accident which could also relate back to excuse number 1,lol.

[flyguy]

Re: Concerning Vne

Well. here is the story that prompted the question. I was up at about 14,500, fooling with the mixture control and such and got finished and started down. At about 11,000 I got really bored with the time it was taking so I decided to do a few turns of a spin to dump some altitude.

So I do my standard entry (which was probably not the best idea) and we kinda roll over the top starting to rotate when I hear this loud metallic ka-bang behind me. My first thought was that the tail had come off. I just said to myself, "I guess I am dead." Only time in my life I have been scared when I was PIC.

Of course I look behind me and I see my two aluminum chocks are plastered against the opposite side of the baggage compartment from where they were, way up on the side of the canvas bag. I had somehow pulled negative Gs and then the rotation slung them across the baggage compartment. Never had that happen before; don't know what I did different that time.

By then I had let off on the controls and the plane had recovered from the spin and was going straight down, about 10 degrees or so past vertical. I immediately start a measured recovery from the dive and as we go past about 30 degrees nose up the airspeed pointer swings up to exactly 140 and then drops down.

The plane is fine of course, and the only thing that bothers me is not that I got to Vne, but rather that I got there by making several mistakes and one of them I still don't understand. Sure put me off spins for a while.
DC

[M Towsley]

Re: Concerning Vne

Hey DC,

Strictly a slightly informed decision after reading about how these planes were load tested, but I think they would be conservative on their numbers. Knowing that some pilots would push the envelope they would want some cushion before something fell off. Then again, people back then were probably more conservative overall and the company did not fear being sued as much as they would today. Just conjecture on that last part. Forrest would probably be a good source if he catches this thread, sometime.

[Forrest Barber]

Re: Concerning Vne

Here I am! last post of the day. My Father , Al Barber, test pilot in the 40's did the dive tests on the D models. He took them to Vd which is 10 % over Vne . Never had a problem . When i was testing for Mrs. Feris ( this is all from memory) I merely took them to a Vd of 154 mph ; 10% over Vne 140 on the prototype. On thing I found strange there was no required testing of a rolling pull, Vne and then pull 5 g's straight pull no roll with aileron.
NOW for the Swick T clip wing ; I can state for a fact that at 140 straight down and a push to inverted at 170 level inverted , the leadings edges will pop loose and scare the H out of you!! We modified the LE attachments and I put a personal Vne of 160 on the Leise Marie . ( The 180 HP clip I flew in shows and show athe fly-in each year). e-mail me direct for any information i may have from the past...
At the fly-in at Alliance last year I could only do some pussy cat stuff ; the aileron hinge brackets were too loose on Leisa.... No snaps for sure.. dinner calls...