Flutter Testing the Gee Bee Z - Conclusion! - Leon Tolve - Part Two

[@Pilotc180]

Thank God for the few men like Kermit with the passion and the means to save these aircraft and share them with us👍

[@nakinajay]

“ Pretty good for an amateur “ haha I’m dying. Such a wonderful, sweet gentleman. Rest easy big guy. You are sadly missed

[@stevem8825]

Kermit, thanks for posting these two video's. As an aero engineer, I am familiar with some of the papers that Leon Tolve wrote on flutter and it was fascinating to see him in person and watch him work. Old masters like this are hard to replace ......

[@peterlastrucci324]

You have done so much for the preservation of aviation heritage Kermit and taking Leon in the 51 was very special.. 10/10!

[@babaganoush6106]

He must have loved being taken up in the Mustang. And aerobatics! both of you had balls of steel. Kermit you not least for taking an 82 year old gentleman up and making it very real. Well done.

[@outofcomms]

This was more commonly known as a GVT or ground vibration test, a flight flutter test would generally follow. The shakers are 1/4” Stroke, they have an output of only 5 to 10 pounds of force. It doesn’t take much to influence the resident frequencies of the airplane. Initially white noise is fed into the airplane and the accelerometers will pick up those frequencies. He will then home in on those frequencies and measure amplitude. This process will be done on the wings, horizontal stabilizer and vertical fin as well as control surfaces. It is these frequencies that the pilot needs to avoid, usually by avoiding certain RPM, adding mass or design change. I was very fortunate to work for Sandy Friezner of Specialized testing service Arleta, CA for 12 years and conducted hundreds of GVT and flight flight test. Watching this video brought back a lot of great memories. Thank you very much, Joe

[@dnbeckmann]

Your all's work on that Gee Bee is a significant part of the history of that airplane. Thank you.

[@leonaparsons3629]

men like leon are and were priceless! another greaqt person that kermit showed us. thank you kermit from another Leon

[@jonpardue]

Wonderful to see quality engineering work done so the real answers come forth. A fitting tribute to Leon Tolve.

[@ChrisB257]

Thanks Kermit - this was totally fascinating. Leon was a very talented man - RIP.

[@rexmyers991]

Extremely well edited. Very informative and a great tribute to Leon. My father taught B-25 bomber crews during WWII. He was in the training command in Texas and had access to almost all types of AAF aircraft. He said flying the P-51 was his greatest thrill. Thanks, Leone, for making it safe.

[@warped-sliderule]

I recognize some of his basic and old equipment. From that can infer how deep Leon's grasp of the physical principles must be. What a brilliant and humble fellow, exemplifying the greatest generation. Your work has saved many lives, rest in peace Leon. Kermit thanks for the video. From the science perspective it's one of your best...

[@badazrod]

Two things Kermit! First, To be among those AMAZING people! Just wow! Great fortune! Second, Thank you! I understand flutter and flutter testing so much better now! Maybe I can learn more! BTW, splitting the weights is very similar in practice and theory to splitting the weights from static balance of a car tire to dynamic balance of it. After this and other study, I agree that the original fluttered. It looks like the other wing was starting to fail. It is such a shame this was not known then. Thanks again for all you do for flight! :) God Speed Curtis and Leon!

[@JPR3D]

Wow, not only does Mr. Tovle really know his stuff, he explains it so easily. Thank you for uploading these archival videos.

[@daveprtr]

Thanks for showing this Kermit .. The world was lucky to have the talented Leon at a time in history that required superb engineering know how.. May he forever Rest In Peace in the thought he did his job and carried it out so diligently ..

[@artd.]

I absolutely love your certification procedure, "Me and God"! Great video Mr. Kermit. It seem that with today's electronics some one could build a much simpler and cost effective equipment to do flutter testing. Every high performance builder should watch this....Thank you Mr. Kermit.........:-)

[@flynfishak]

The Art and Science of Engineering in all its glory. Those guys were jewels if you could find them. What a fun and educational experience with such a huge wealth of knowledge.

[@JoeGator23]

Leon Tolve lived another two and a half years (May 2004) after this video was made (Nov 2001). If you watch him at work, he was a master of his craft and his analytic / mechanical skills are an art that has now slipped away with his passing. It is amazing how his talent and experience of "hands on" engineering evolved to what it has become today in the digital world... and that he could diagnose and solve problems the with his expert skill set 50 years ago. We lost a national treasure with his passing- teach your children well. RIP Leon.

[@The_Modeling_Underdog]

Agreed, the man is an orchestra director. Clear, to the point, not a single word or gesture wasted.

[@TPath3]

Today with analog-digital interfaces you could create a three dimensional picture of all the Accelerometers - back then you didn't even have an electronic calculator - one needed more in depth knowledge, experience AND imagination to solve problems. But of course top-notch engineering today is far more demanding because the problems to solve are many more in a far wider field - it's like a huge pyramid whose foundation rests in the past - many are totally unaware of this until it's gone when they realize that they have lost everything - and bringing it back will cost them mountains of effort and money !

[@The_Modeling_Underdog]

@@TPath3 truer words have not been spoken.

[@JoeGator23]

@@TPath3 I think you missed the entire point of the comment... I would be curious as to any actual physical aptitude that you possess equivalent to diagnosing and solving any of these problems without using computers? In 50 years you will be irrelevantly replaced by the latest software package upgrade compared to Leon's trailblazing craft and his lifetime contribution to it's advancement. What will you ever do besides praise technology over human technical engineering capabilities while leaving no legacy for yourself? In an indirect way, you are part of the problem, considering you and your laptop think you already know everything... but would have no clue as to actually solving any real problem on your own because you have no deep hands-on experience, relevant human insight or ability to physically build, test, experiment and improve anything in the real world on his level. People's lives depended on his work constantly in a field that he essentially developed with his peers. I'd chose one Leon over 20 of you techies any day. That old man would have smoked you.

[@olesarge1724]

Mr. Tolve played a huge part in our history. Kudos to. Kermit for spotlighting such an important part of the WWII effort.

[@tamasregert5697]

These two videos have inexpressible value to the engineering community. All your videos are exceptional and unique. All my respect to you Kermit for what you do.

[@ichi-goichi6184]

Kermit thanks for sharing this video of Leon and his contribution to aviation. A true unknown hero! Thanks again!

[@KPMACHINE1]

THANK YOU Kermit for posting and sharing! Most of all THANK YOU Leon for your service to your country and to the science of aviation.

[@flyinhawaiian5848]

One of the smoothest Mustang three point landings I've seen in decades! "Pretty good for an amateur!" 85 years old (in 2001), and his fertile mind was still sharp as a tack! RIP Leon

[@larrymacaluso9051]

I really enjoyed these videos, it shows real dedication to the science of flight and how it was and still is made safer with each engineering test. Thank you Kermit for sharing it and THANK YOU Leon for all your contributions.

[@drwhat4395]

That was a great video. That was great of you Kermit to help Leon feel useful before he passed. His expertise will be missed.

[@justaskmeiknow5584]

Leon's a good guy with a great sense of humor....RIP

[@rbuggs3658]

Thank you for honoring Mr.Tolve. What a great man! And Thank You for sharing your wings with us ground based folks. Please park the Gee Bee Z and let it be used for our imaginations... We want you safe...

[@Hopalong..75]

The P51 is so crisp, and perfectly detailed.

[@MatthewRulla]

I was hoping to hear some comments from Curtis Pitts while he was there. Both Leon and Curtis are legends and their contributions will always be remembered. Thank You for making this footage available!

[@KermitWeeks444]

Curtis is getting his own video, coming up in next few weeks.

[@bicycle697]

What an amazing man! Thank you Kermit for showing him to us!

[@dianeswift]

Again, thank you for this incredible historical documentation. You're a great one, Kermit. (As was Leon.)

[@billroberts9182]

My father graduated from Caltech in 1945 and 1946. I'm so impressed with Leon's humbleness and expertise. Caltech has been a beacon of scientific and engineering knowledge. Great video series!

[@ChosenWon]

Best video ever. Super informative and a pleasure to watch. Thank you.

[@terrancealexander5621]

At 80 I have always been an aviation nut and anAF aircraft mechanic during Vietnam. I found it extremely interesting learning a little something about wing flutter and a great engineer Mr. Solve that dedicated his life's work to solving to wing design problem. I will never think of an aircraft again without thinking of Leon Tolve !!

[@daviddowney9331]

So little credit given to those engineers and scientists scratching the path into the unknown. My heroes.

[@wtwombo5445]

I believe the “payment” for the engineers, and Maintainers, was the, Continued, lives of the Aircrew, who survived to Fight, for Home, And, hearth! and, the grandbabies!

[@dankap10]

Sir, this is one of the best videos I have ever watched on KZbin! Thank you

[@michaelmartinez1345]

What a great program this was!!! Wow... There is so much that went into designing and building these machines... The science of recognizing vibration and how to control and dampen it, is an entire skillset itself... This program reminds me of the problems the BD-5 kitplanes had with torsional vibration of the shaft driven propeller... It was so bad that the propeller, the shaft the timing belt and pully's and the engine had been negatively affected in a relatively short time, like 40 hours....Finally, they hired a specialist like Leon, who found what caused the issue, and eventually they came up with a sollution... Thank you for presenting this excellent program... All of you who were on this program, are genuine aviation legends....

[@fostercathead]

This literally brought tears to my eyes. Thank you so much!

[@dallasboricua21c]

These men were jewels of our past... How fortunate to have had him this long...

[@Flapswgm]

Why is it this guy isn't working with YOUNG PEOPLE to maintain this quality of knowledge. WOW! I wish he was 50 years younger and I was in his class. THANKS GUYS. This was INCREDIBLE.

[@johnfalkenstine8377]

Kermit, thank you for posting this. As a result, I downloaded a huge bunch of old math data concerning this situation. I remember flying to Trinidad in the early nineties on an old tiny Learjet. The plane had an issue and would drop a wing and an alarm went off up front. The pilots would catch it and things went back to normal. After a while, the wing would drop again. I'm sure it was a serious problem but the pilots just caught and went on flying. So airplanes are really extreme engineering, even though they appear simple. This old man is just terrific.

[@Chakirisan]

What an amazing man, loved watching him work.

[@Jack-Wall]

@22:59 - triggered a memory of an engineering mentor I had way back when .... I recall almost exactly the same words spoken to the word with the same intensity and ease ...... Salute Mr. Tolve ....Those we remember and learn about are not gone at all even though they may no longer be here.

[@mikeoswald8053]

This is excellent. I used #1 to introduce students to flutter (something not taught to GA students) and the reason for the aileron weights, etc. I will now request they view#2 and do some reading. Thank you Kermit for publishing this and thank you Leon for your years of work.

[@hazelnut49]

Thank you Kermit Weeks for these informative videos that help explain wing flutter & explain what happened to the original Gee Bee Z & later your friend. I hear their is an article in the latest Air Classics about this too that you helped with & that more information is to be revealed later. The work you & Fantasy of Flight do to keep the history alive & to educate the public on aviation is remarkable. 🙏

[@Angelum_Band]

We need this type of analysis as it's explained more often. Excellent!

[@JoeLinux2000]

Not many people understand it. In this case the trick is inducing artifical flutter into the plane and then measuring it. They don't explain exactly how to correct it.

[@Angelum_Band]

@@JoeLinux2000 They actually did: adding counter weight which they said they were not going to do to preserve the integrity of this relic. Kermit mentions flying it below 200Mph or Knots can't remember. In any case Kermit is of the few who could but shouldn't fly this thing for the same reason.

[@givenfirstnamefamilyfirstn3935]

Did they change their mind about external aileron balances before deciding to do nothing?

[@Angelum_Band]

@@givenfirstnamefamilyfirstn3935 Kermit mentioned something like a detachable counter weight so it can be removed for display. Honestly I would not fly that airplane even for million dollars. I appreciate the machine, the effort the people that made it put in and the extreme it was taken to back in the days but, I would leave it there for people to admire. As a perfectionist I have learned that 99% when repairing something is good enough to survive another day. My humble opinion.

[@dennisjay3277]

Leon had to be in his eighties. Just take a look at his penmanship. His numbers and letters so precise. I know we didn't get to see all of the day but he was so sharp, with his explanations. The reason he didn't charge you Kermit was he got to use his knowledge one more time. He got to feel useful.

[@thomasaltruda]

29:17 “Pretty good for an amateur!” Haha love it!

[@terrygrady7683]

Another legend who advanced aviation. Great vid.

[@leet2089]

I love aviation and stumbled across Mr Kermit Weeks channel a few weeks ago How did I not know about this amazing guy!!!? What a fantastic collection!!!!! And he has a real down to earth vibe Totally binge watching all the episodes Huge fan now and a def place to go on my bucket list Keep up the great work!!!

[@KermitWeeks444]

Thanks for finding us. Be sure to subscribe.

[@leet2089]

@@KermitWeeks444 Wow ! thank you so much for the reply Made my day😀 Def subscribed and waiting for the next video🛫

[@MililaniJag]

Great vid! Leon Tolve a Steely-Eyed Aeronautical Research Engineer. All in aviation owe him and his colleagues a huge Thanks!

[@ednesbit2988]

Thanks for sharing this !!!!! it was one of my first models I built as a kid back in the 1960,s I believe that time period !!! Brings back so many memories of all model airplanes hanging in my bedroom ceiling my dad was a pilot he owned a stearman and a j-3 cub loved it

[@alanluscombe8a553]

Gee bee is such a unique amazing aircraft. I love the z model and r1 r2 so my CV. When I was nine I met Delmar and he allowed me to sit in his geebee I will never forget it

[@blancolirio]

The boys are barely keeping up with what Leon is putting down…..me too!

[@NesconProductions]

Have to know the right frequencies Juan ;-), the exact science (with slide rulers not depicted here) goes over my head as well (but interesting old-school education never-the-less..). Best wishes to you & family to get some much needed precipitation your way.

[@colinwallace5286]

I had a thought that perhaps in the early days of aviation, they only thought in terms of symmetrical movement of wing components, and didn’t happen onto the concept of torsional movement as a failure point. It was unlikely that they could retrieve enough wreckage to know what failure took place in a crash, and if the plane DIDN’T crash, they likely took that as a sign that all was well. That’s likely oversimplifying, but it’s what I thought.

[@stephencampbell9095]

I sure hope Leon is teaching you this magic.

[@colinwallace5286]

@@flyingroark I somehow think that Kermit Weeks is not one to fall for assorted forms of “snake oil”. Is it not also possible that all of the things you listed are minor players in the big picture, that the issue they are chasing shows itself regardless?

[@colinwallace5286]

@@flyingroark Could be. I consider the number of times that someone decided to simply jump from the theoretical/virtual world straight to cold hard reality, and discovered something vital that they either missed or didn’t account for, with disastrous results. Sort of like how a fossil with a decent multimeter finds the issue that technology was fooled by. If you were paying attention, you would have heard them say that they weren’t willing to destroy the essential essence of the aircraft by trying to fix something that would only appear at near limits of performance. It DID result in some sober consideration of priorities, which is likely just as useful in the end.

[@ianrenshaw6653]

Thank you for these wonderful videos! Thankfully these priceless aircraft are in your expert and loving care! May they be around and enjoyed forever!

[@vikmartin-more4735]

Wonderful story and history lesson. Thank you Kermit for sharing.

[@divyajnana]

Hadn't seen this one. Great watching the best in aeronautical engineering at work. Fantastic video. Thanks Kermit.

[@novanogo07]

Super cool for Kermit to document this. I'm in over my head, but it's super interesting.

[@walt8089]

Great video, Mr. Tolve seems to have been a gentle, kind and very giving man.

[@jackdedert2945]

I love to see that Crown DC 300 amplifier apparently driving the vibration actuators. They used those things back in the 60s/70s to position X-ray tables and heads. They would take any DC or AC signal and amplify it to 150 watts x2. Of course they also drove a good percentage of the sound reinforcement industry as well. They're still coveted by a segment of audiophiles even today.

[@Flapswgm]

What an inspiration. Is it possible we can live up to his expectations today? I would like to say yes. We will see. God Bless you Leon.

[@mriamilne]

Fabulously put together videos. Immensely informative and entertaining. Ty.

[@jwingo7257]

Old school analog electronic analysis. This and slide rule were the sort of genius that helped develop radar, advance aeronautical engineering and ultimately win the war. The needed nerds of Bletchley Park and MIT with their pocket protectors, slide rules and coffee then went on to put us on the Moon and win the space race. Hats off..

[@artd.]

Every high performance builder should watch this......:-)

[@stevejones9044]

Kermit my hats off to you for commemorating Leon like this. Thank you.

[@freemandecker8584]

Thank you Kermit... Nice tribute to Leon... one of those people that contributed to the success of Aviation... as for the Gee Bee Z... it would be a good time to modernize the airframe from the ground up... a modernize replica of Gee Bee Z...

[@bjofuruh]

I `ve had a couple of RC model planes destroyed by wing flutter. I can testify that it is like an explosion. You hear a sudden roar, maybe half a second - and then - BANG. The wing is gone. Only a shower of balsa and covering material trailing behind. A good thing that smart guys like Leon have developed a method of detecting and rectifying this dangerous situation in full scale planes.

[@leezinke4351]

Geebee is such a beautiful plane!

[@richardperry21]

Wow, thank you, Kermit, great video!!!!

[@peterlewis7292]

Good evening Mr. Weeks, My goodness what a science and what a teacher you had. Many thanks for your time to post this very important film about the causes of flutter, very interesting and I only wish I could understand some of the calculations that went behind this science. Rgds, Peter.

[@pjv767b5]

Very interesting and amazing what these guys learned using very old school equipment.

[@YouTubeCatEngineer]

This was fascinating Kermit. I'm an aerospace engineer, structural analysis (Boeing, Cessna, etc) and I've had a long-standing dream to design my own sport plane. Flutter has long been a concern of mine. So excellent to see a full-up ground vibration test in action with a master like Leon. I experienced slave strut flutter on the first plane I owned an experimental Pitts S-1S (builder Lloyd Stoops, CO) and it scared the H3LL out of me. I added the aerodynamic trip on the struts and stiffened up the torsion at the upper connection with washers/shims to solve that problem. Later I bought an experimental S-2B (builder Bob Ernst, FL) with the same issue. I duplicated the aerodynamic trip measured off of a factory S-2A and also tightened the upper connection in torsion and it works perfectly all the way to redline airspeed. Thanks for sharing these videos I know they take lots of time. I have entertained nearly 20 million people with my own KZbin channel and the ad revenue is not good at all. PS great to see Curtis in part 1!

[@Skinflaps_Meatslapper]

Flying wire vibration is a fun thing to watch in an agcat, it usually stops when you land.

[@kimkeam2094]

Fascinating subject, reminded me of the equipment that I had been trained on and still own!

[@ronaldjennings8057]

Kermit that was a very good educational video finding the problem before the problem find you. I hope you're doing well in Florida one thing I will say my friend please be safe that viruses is still there hopefully we can get that under control I want to see your fantasy of flight to come true and yes we all on borrowed time be safe be careful and God bless🙏 my friend we're losing too many Pilots🛩👍

[@Fonseeker]

Wow this was awesome, Thanks to Leon Tolve for sharing this amazing knowledge. May he RIP!

[@lewis730]

Outstanding content Mr. Weeks. Thank You!

[@fredericrike5974]

Awesome engineer whose work was instrumental in the sciences that would let a plane fly faster than sound to fly safer than ever before, to create the civilian airliners and the world we know today. A stunner for more than a half century. Thank you, Kermit! Men like Leon are what we hope our children will aspire to be- not a better example out there! FR

[@williamtorp2817]

Thanks Kermit. I am a big fan of your channel, especially when the technical aspects of flight are covered.

[@foehammergaming309]

Wow what a gentleman and a scholar. Literally! Great video extremely interesting

[@barrysheridan9186]

Excellent to gain some insight to the flutter phenomenon. Thank you for this video.

[@1mmickk]

Nearly 200 years of experience there, all looking at Leon like hes a cross between a Witch Doctor and a Mad Scientist. RIP Leon.

[@frankienv3906]

Another Great Mind and Great Engineer we will never see again. 🙏😢

[@aviation3530]

"Pretty good for an amateur". Haha. I think Leon was having a great time. Thanks for sharing.

[@theoldbigmoose]

It was good to see the amount of respect you gave Leon. He was still so sharp. The instruments were old, but he sure knew how to read them. What a great man! Thank you for preserving and sharing these videos. By the way, what has the last 20 years wrought with this Gee Bee Z of yours?

[@jhaedtler]

Fantastic video, Thanks so much!

[@techsolutions8237]

Hardly got the gear up before Leon was asking about aerobatics...👍

[@jedheath7329]

Love it Happy a proper enthusiast is looking after these fantastic aircraft Cant wait till we can visit again from uk

[@abundantYOUniverse]

This was fascinating and fantastic at the same time, thanks Kermit!

[@colinwallace5286]

What boggles my mind is that Leon and his companions came up with a way to test their theories and answer their questions about aircraft. But the most amazing aspect is that they figured out how to interpret the results they got to come up with possible fixes. I wonder what Delmar thinks watching this. Must be a bit jarring. That old film, seeing the wing mostly gone. I can’t imagine the sense of horror that pilot felt in the last few seconds before he hit.

[@GordonjSmith1]

Really very interesting / informing! For a very clear example of the impact of harmonics on structures there is no more famous example than the Tacoma Bridge disaster, although the foot bridge across the Thames in the UK is almost as instructive. For owners of grandfather clocks who's houses are carpeted, it is the reason the clock needs to be firmly attached to the wall (if not the pendulum can 'rock' the clock on the carpet and bring the pendulum to a stop).

[@steveshoemaker6347]

God Bless....Leon Alfred Tolve he has save many lives......Thanks Kermit for posting this fine video...👍👀

[@pauldavis4656]

Amazing men with amazing passion! God Bless all of you!

[@robertsanders6463]

Wonderful video, I really injoyed it, a real pioneer!

[@MsEagle65]

Thanks for the great Video. Reminded me when I was studying, all analog equipment.

[@schecter6l6]

Elevator flutter is what occurred on the Galloping Ghost P-51 at the famous Nevada Air Race to Jimmy. A sudden 7 G climb due to elevator flutter (asymmetric) coming out of a turn pitching nose high causing the elevator trim tap to depart the plane under the high load.. Jimmy passed out no doubt due to high high G-forces and the rest is a tragedy! ..Makes me wonder how many of these guys that chop their wings do these flutter tests..Thanks Kermit for posting this always interested in seeing another dimension in aerodynamics..

[@fredferd965]

You gave him a good flight! It's things like that that are important.

[@arnomaas6452]

I wish Mr Tolve may Rest In Peace ! His work saved many lives !

[@hieronymusbosch693]

ok your first P51 ride...here we go...one can only dream

[@FlywithMagnar]

Kermit, I love your videos! And by watching this video, I had learned something new.

[@gordonquickstad]

Nice. Thanks for making it available.