Investigating what looks like a Serious Problem in Modern Cubs

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Addressing what seemed alarming that we (and you guys) noticed regarding the tail. Proudly associated with ForeFlight: www.foreflight.com/flightchops
In this episode, I’m building solo time reviewing the #SuperPatriot, the latest #STOL #SuperCub variant on the market. We documented what appeared to be an anomaly with the tail during full power static take offs, which raised a lot of alarm bells in the comments of the previous episode - so we’re doing a deep dive to investigate it further. Dave and I had a lot of fun and both of us became quite comfortable flying this airplane during the course of the month that I had it at home. Over this and the next episodes we’ll share more detailed thoughts and opinions of the handling characteristics, maneuverability and speed range envelope afforded by the Super Patriot STOL Cub-Variant.
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FLIGHT CHOPS DISCLAIMER:
I am a "weekend warrior" private pilot, I fly for fun with no intentions of going commercial. I have had my PPL for over 15 years, but still consider each flight a learning experience - I generally take detailed notes after each flight to remind myself what went well or what I could do to improve.... Having GoPro cameras to record flights like this is invaluable. I find these self analysis videos very helpful in my constant quest to improve, and am happy to share. Feedback is invited; however, please keep it positive.
Visit www.FlightChops.com/ for behind-the-scenes content, epic giveaways and to search episodes by aircraft type!

Опубликовано:

25 авг 2022

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Комментарии : 200

@scotthunziker3506 Год назад

Oh gosh, please don't call the tail motion "flutter"! For the last 40 years my job has been the prevention of flutter (that is, aeroelastic instability) for military and commercial aircraft, using sophisticated analysis, ground test, and flight test. If you got that Cub going fast enough, the tail would inevitably flutter and come off. But that's not what you're seeing in these videos. It does seem like a lot of motion, but it's a dynamic response to unsteady loads. Flutter is a very different phenomenon, involving self-excitation.

@FlightChops Год назад

Thanks for the insights here. I think it is safe to say a lot of GA pilots, myself included could stand to learn more about what “flutter” really is.

@9HighFlyer9 Год назад

I haven't watched the whole video so maybe it's covered. To me that definitely wasn't flutter because only a kite would flutter at that airspeed. Honestly it looked more like a harmonic vibration.

@lvrally Год назад

@@FlightChops I found the following videos worth watching (I'm not associated with either) ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-qpJBvQXQC2M.html&ab_channel=AIRBOYD ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-MtiN48ePYwA.html&ab_channel=KermitWeeksChannel-Over340VideostoSee%21 (part 1 and 2) love your channel!

@NobleWizard Год назад

Correct me if I'm wrong but flutter occurs at high speed when a control surface has play or not balanced correctly. On the cubs it looks more like the tail plane reacting to the vortices from the prop and wings if it's only happening at low flying speeds.

@FlightChops Год назад

@@NobleWizard you are correct - I should not have used the word flutter - but I think Don pretty much explains what it actually is.

@-Spatz- Год назад

Awesome meeting at Airventure, FlightChops! Great video as always!

@bnelson313braveheart8 Год назад

Nice video! Loved the peek of the RAV4 paint scheme.

@erric245 Год назад

Great work as always, Steve!

@clarencewiles963 Год назад

I bet you had some fun, family with friends. Thanks again for your work.

@michaelguy7168 Год назад

More flight chops please, love your video’s.

@brianlarson5006 Год назад

You're good with the vibration, man. I was a Production Test Pilot, Ferry Pilot, Factory Flight Instructor, and Assembly Technician at Cub Crafters from 2007-2011. The key on preflight with the Carbon, Sport, and Tops is to watch the forward and rear attach points where they mate with the fuselage and jack screw assembly. A little play is normal on an aged aircraft. wiggle your horizontal up and down, forward and aft. On a new aircraft, there will be a bit of flexion but it shouldn't feel loose and you shouldn't be able to see the carry through rod. On a higher time aircraft, consult your maintenance manual. I believe it's between 1/16"-1/8". But again, consult the manual or call the factory. Every now and then, take a peek at your jackscrew as well. Its simple It's 7 or 8 screws on an inspection panel. Your choice on the left or right side. You can see it from either. If it looks off, call your A&P. Too easy. Finally, every now and again. cycle your trim through full range. In the Top Cub, crank it while you are standing outside watching the horizontal articulate through its range. If you get any indication of it slipping or ratcheting, investigate prior to flight. Sport and Carbon are electric driven. If you see a ratcheting motion as you manipulate it or the motor sounds strained. Investigate.

@pontier09 Год назад

Brian, I have seen an experimental cub with a stabilizer attached to the trim system stabilizing the horizontal stab on the underside like a strut - have you seen this? I can't track down which manufacturer was doing this.

@brianlarson5006 Год назад

@@pontier09 I have not seen that. I can try to do some research and find out. Being that it's experimental, it could be a one off mod.

@pontier09 Год назад

@@brianlarson5006 I have a photo but no way to share

@FlightChops Год назад

Thanks for sending the image via Instagram messenger - it does look like a one off mod. I’d be interested to see if it creates different stresses by trying to hold it. And the way it works with a channel cut through the fuselage for the triangle brace to be able to slide up and down wit the front of the stab when the trim is used seems like it could introduce new problems such as back country debris getting into the rear section of the fuselage.

@pontier09 Год назад

Brian it was Crosswinds Stol that make the trim connected horizontal stabilizer strut

@billbrisson Год назад

great episode! I've been thinking about updating the paint on the Raven, and I like the scheme on your 14, I may just steal elements of your design when I repaint my RV6 :)

@ChrisB257 Год назад

Great vid Steve - looking fwd a lot to the next one :)

@goatflieg Год назад

"Hey, I've been to that airstrip! Wait a minute... that's ME at that airstrip!" Wasn't expecting that shout-out; thanks! I was wondering why I never noticed the horiz stab movement, but I was looking at a strange viewfinder at the time. Interesting that it's a non-issue; rather counter-intuitive, but glad it was very carefully engineered. Glad you were able to address the control stiffness and that it was a servo issue that can be corrected.

@Frankestein01nl Год назад

Good thing showing how Dave mounts the aircraft, i had no idea about getting in ;)

@paulcarstens2601 Год назад

Very clear flutter explanation. Thank you Steve!

@kevinphillips9408 Год назад

Really enjoyed this video. Thanks

@SoloRenegade Год назад

trying to needlessly stiffen things and make things rigid causes all manner of problems including failures elsewhere in teh design, as well as adding needless weight. It's ok for things to flex if designed for it, and fatigue life has been evaluated.

@benjaminsmith4058 Год назад

Flex and flutter are two different issues. Flutter suggests an aerodynamic design issue. For example, airline wings flex a lot (especially the 787 wings) but that is different than flutter, which involves rapidly oscillating. In fact, make something stiff so that it becomes harmonic with the driving force can induce flutter. Many studies by NASA has shown just how dangerous flutter is. There is no good flutter.

@garyjohnson4575 Год назад

...feathers flex!

@SoloRenegade Год назад

@@garyjohnson4575 exactly!! nice to know I'm not alone out here 😀

@transcendedanal7307 Год назад

@@benjaminsmith4058 You replied to the wrong comment my brother in christ

@justflylow Год назад

I really enjoy your videos! I wish I was able to fly half of the aircraft you have flown! You are a lucky man. I really want to own an RV someday and watching your videos of yours has really cemented my desire! Happy flying my friend!

@FlightChops Год назад

Thanks a lot - glad you're enjoying the videos! - and for sure yes! Van's had the perfect balance of aircraft that cover a good range of the spectrum of flying I think most GA pilots aspire to do. The RV-14 is an amazing traveling IFR platform for 2 people + 100 lbs of bags... OR if I feel like having some fun, I can dump the luggage, do up the 5th point (crotch strap) on the harness, and go fly aerobatics :)

@justflylow Год назад

@@FlightChops I have been interested in them since they came out with the RV 4. I would have been interested in the RV 3 but it is always nice to have the option to take someone with you even though I usually fly alone. Now there are so many models to pick from. Great company!

@Tracomaster Год назад

that callback to the old supercub was awesome! recently watched the episode where someone broke the thing and wondered what came to be of it.

@FlightChops Год назад

Yeah - it took a couple years to get it back online - it is operated by a small private club now.

@WideLoad405 Год назад

Paint scheme on the RV is reminiscent of the Harvard you flew. I dig.

@andydelarue9344 Год назад

Test pilot Dave is a cool dude, good team

@westnoble1020 Год назад

Is that the same grass field from the Zen video and others with FKO? Looks so different now. Awesome video. You've pushed my love for Cubs.

@i.r.wayright1457 Год назад

A couple scenes at the end were at the birthplace of the Cub. Lock Haven, PA, former home of Piper Aircraft. There is no mistaking those bare rocks on the north side of the hill. Now, picture it is June 1972 and there is 12 feet of water on the field, and 160 plus planes. I was there during that time.

@AlexFeldstein Год назад

Loved this one Steve!

@FlightChops Год назад

Thanks Alex

@stonebear Год назад

Skylanes and even L-1011s do that too stab wobble too, only on landing. When you get those big Fowlers putting turbulence across the tail, the horizontal stab is *gonna* waggle, and in a Skylane (one that has a back window, anyway) you can turn around and *see* it on final, and you can feel it in the seat of your pants... First jet I ever rode was the aforementioned L-1011; I was aft of the wing and could see what was going on, and when he set full flaps I felt that familiar rumble in my seat and I'm like, this feels *exactly* like the ol' Skylane.

@GaryLaaks1 Год назад

Same reason why bridges flexes when a heavy truck passes over I guess.

@maxflight777 Год назад

I love the name, super patriot!

@markthibault8579 Год назад

Flexing metal can be off-putting but if engineered properly, no issue at all. The Zenith design, CH 601, had hingeless ailerons using flexing metal instead of piano hinges. I was surprised at how this was possible given how many cycles of bending would occur during the lifetime of the part. Quite impressive and well-engineered.

@FlightChops Год назад

Wow - I hadn’t heard about that design for hingeless ailerons - that does seem unsettling.

@givenfirstnamefamilyfirstn3935 Год назад

Were they iron alloy or aluminum/ium alloy, one has (within limits) fatigue resistance and one doesn’t.

@rcsupercubbuilder Год назад

That tail flutter has been around since the 135hp cubs, it was more pronounced with the 150/160s and the 180hp really started shaking it. There are brace systems made here in AK that do work with the jackscrew, but most of us alaska cub builders don't see the need even with the 200+hp engines getting stuck on the cub builds now days. With proper fuselage horizontal attach bracing, tight tolerances in the jackscrew, and proper tensioning of the wires it really isn't that bad. Go look at a 180/185 crank up on the ground at full power. They shake just as bad or worse.

@earlebubar1805 Год назад

This is really a design flaw by Piper, they were to CHEAP to design new longer brace wires and make the attach point further out........ PA-18 wires are same as J3 wires that were designed for the much smaller unbalanced feathers. Had they extended the brace wires to the same position from end of the horizontals , it would have removed ALOT of the shake. I saw a Super Cub modified that way in Alaska . So asked the owner how much difference it made. He said it was 50% better.

@foesfly3047 Год назад

I hope we get to see detailed footage of your RV14 with its stunning new paint job.

@FlightChops Год назад

It’s coming :)

@foesfly3047 Год назад

@@FlightChops Cool!!!

@AugustusTitus Год назад

Neat to see an airplane from Helena on a Canadian channel!

@197SqnATC Год назад

Love that altimeter tape watch face! What watch is that? Unfortunately couldn't find a similar face for my Huawei watch

@aevdave Год назад

Check out the Husky tail, at least on the older ones, there is an additional rod brace to the leading edge of the horizontal. Trim system is considerably different.

@RubyS.1 Год назад

It's how teacher described it the way they build high rises in San Francisco and Japan were they actually move quite a bit because of harmonics.

@benjaminsmith4058 Год назад

What you are describing is flex. Flutter is like what happened to the Tacoma Narrows bridge, which didn't end well.

@jamesringler987 7 месяцев назад

Does the bearhawk style elevator flutter or does the new design eliminate it

@carykong Год назад

Sailplanes must always consider the real possibility of a short low energy landing in a confined space in s farmers field, under a power line, short of a ditch Relatable to stol flying. Good subject for future content.

@AV8R_1 Год назад

I admit, I saw that in the last video to, but I didn’t think anything of it, because it doesn’t look to me like the tail is fluttering. It looks like it’s vibrating, but the frequency vibrations along with the frame rate that you are recording video makes it look as if the tail is fluttering.

@stevetomassetti4420 Год назад

Curious. I built a 3d printed J-3 piper RC model that does the same tail flutter under static engine tests. I just added struts to tame it.

@tk27a Год назад

As usual Steve, your footage from many angles was of first class quality. I'm intrigued how you were able to set up all your cameras and gear on a no. 1 serial aircraft. I would be very interested to see and hear from you: how did you secure your cameras for the flight? A kind of "making of""

@blake.crosby Год назад

The 3M sticky tapes are strong enough to hold everything in place. Even the externally mounted cameras. A lot of RU-vidrs use this non permanent method of attaching cameras to their aircraft.

@tk27a Год назад

@@blake.crosby I suppose you are refering to the 3M (red) VHB tape to stick a GoPro mount piece?

@blake.crosby Год назад

@@tk27a yup

@tk27a Год назад

@@blake.crosby Thx. Now, in order to get the perfect angle with this sticky tape on the first time, this is what we call "experience". Unless Steve then put a swivel on this mount which again I would be curious to see.

@blake.crosby Год назад

@@tk27a the go pros have a viewfinder to help you frame the shot. Additionally the fov of the lens is so wide... It's hard to screw up.

@jeremykemp3782 Год назад

Nice vid thanks

@rogerbee697 Год назад

B-52s have approximately 30 feet total of wing flex at the wing tip. Gotta have it.

@TRPGpilot Год назад

What's that in metres?

@givenfirstnamefamilyfirstn3935 Год назад

Degrees of difference there!

@greenalan12 Год назад

Flight Chops, love the videos!! *Not being a critic* I noticed you had a wind quartering from the left and you slipped to the right on final.. I was always taught to slip the plane toward the direction the wind is coming from. Thoughts???

@FlightChops Год назад

Can you clarify which timecode you're talking about? The idea with slipping is to put the low wing into the wind while slipping; so if the wind is from the left, the low wing would be the left, using right rudder to slip making the nose point to the right.

@greenalan12 Год назад

8:10 is the reference. You did it as you described it should be done!

@wb6anp Год назад

If you get a chance to do Stol flying again, watch the flaps on the competitors, they usually start accelerating with no flaps then at rotation they pop the flaps down to jump off the ground, It accelerates to TO speed faster and takes off shorter.

@KnowledgePerformance7 Год назад

He does talk about this in the vid...

@owensparks5013 Год назад

5:54

@PghGameFix Год назад

Love the shirt at 3:30. I'm going the other way I guess... I'm a game fix channel who is getting back into flying. I'm building a Sonex (Waiex) and I'm going to do a "Dodo Airlines" theme with it. (From Nintendo's Animal Crossing) Keep up the great vids.

@crtzmo Год назад

Did Dave just close the window?? 😂 A long-sleeve T is the Cub lover’s environmental control system!

@mrbigw100 Год назад

Is the flight in the rv14 with Mika the Austrian pilot u flew with still coming

@aggibson74 Год назад

it seems like every year there is a severe weather event at oshkosh. The lightning of one night last year was insane!

@FlightChops Год назад

Yup - there's always at least one big storm it seems

@jayc4562 Год назад

There is a stc for a strake that reduces the motion on 180 plus hp cubs

@Talasas Год назад

A flight school where I flew a CubCrafters cub had that chromoly tube on the outside edge of the trim section of the empennage crack and break. They assure me it's common and that the fabric is holding it together, I didn't know about the other reinforcement bars in the frame which is good to know.

@GlensHangar Год назад

Hi Steve - I'd love to get some time with you to shoot a video about rigging cameras to C-FMVU, find out your input on the cameras you use, and the pitfalls of action cams. They are so much different from my daily cameras (RED and ARRI).

@niklaspilot Год назад

That's a collab made in heaven! Steve surely has a lot of valuable input

@etienneolivier Год назад

Yes!

@FlightChops Год назад

Let’s do it. The last couple years were challenging, but we can ramp back up a plan to do something.

@GlenAndFriendsCooking Год назад

@@FlightChops Anytime after the middle of September.

@planespeaking Год назад

Couldn't you put a tuned mass damper on the tail inside the fuselage?

@ravimohil8969 Год назад

What settings do you use on the GoPros to get the clarity in your videos?

@earthsciteach Год назад

Huh. I wonder if the horz stab on my Tri Pacer does the same thing.

@shoominati23 Год назад

That stab flutter looks like the one on my RC trainer powered by an OS .40 when I made a flight video by zip tying one of those horrifically bad 'action' cameras to the side facing rear in the early 0000's

@airgliderz Год назад

This is not flutter.

@onecheman Год назад

Damn sexy paintjob Chops! Enjoy it, you totally deserve it!

@akschu1 6 месяцев назад

The garmin autopilot servos use a brushless DC motor with a clutch that disengages. The Dynon uses a geared stepper motor that isn't powered when it's not on. This means the garmin completely disconnects while the dynon/grt/advanced/trutrak you still feel the drag from the gear box working against a non-powered stepper motor.

@FlightChops 6 месяцев назад

Yeah - and what's cool is that as of late 2023, I've learned that Patriot Aircraft took my feedback on this and has switched to Garmin for the current iteration of the Super Patriot.

@coppi60 Год назад

Don Wade is an honest man. My wife and I love his family and his flying operation. He will tell it like it is. and not beat around the bush. If you see him, tell him I said hello!

@jimcripps3612 Год назад

I did a tailwheel conversion on the Super Cub so tell me am I the only pilot who has found the Super Cub hard to get in an out of and that the pitch forces are rather high unless one is fast on the trimmer? Regards, Jim in NI UK

@FlightChops Год назад

Agreed :). I learned the trick over time getting in and out of the super cub, and then had to relearn when I started flying the ones with big tires :)

@diederikschip6190 Год назад

Are you going to use an angle of attack indicator? Of not, why not!? Btw, love your stuff!

@FlightChops Год назад

Thanks - this airplane as well as the RV-14 both have angle of attack indicators.

@jimbe01 Год назад

That appears to be an awful lot of flexing on the horizontal stabilizers, particularly considering the aspect of repeated occurrences during the takeoff portion, something that occurs on every flight made. What is the fatigue limit of the underlying structure give the amount of flexing and occurrence for these flight surfaces? (B-T-W What inspection panels are there on the horizontal stabs and elevators?)

@givenfirstnamefamilyfirstn3935 Год назад

The fatigue life will be established after the first few failure investigations.

@FlyingGrimaud Год назад

I’d love to know after having flown this and other cub variants how this compares. What has been your favorite so far?

@afd33 Год назад

There's one video I'll link to that might be a bit of what you're looking for. It's a few years old though. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-Fx48wP517CA.html&ab_channel=FlightChops

@FlightChops Год назад

I will be sharing more detailed opinions in the next episode - for this one I wanted to address that burning question the first one raised :)

@pi.actual Год назад

You say "Modern Cubs" but the design goes all the way back to the J3 (maybe even before that) If you compare it to say, a Citabria, the Cub has a single horizontal stabilizer section with three mounting points - two hinges at the rear and the single jackscrew at the front. The Citabria has a two section stab with four mounting points. On the early Cessna 180/182's where they used a one section trimmable stabilizer like the Cub they used two jackscrews at the front.

@ricktoberfest Год назад

He also talked about how much more prop wash there is on the “modern”’cubs from increased horsepower. That was the comparison he made to the 1950s cub he leaned tail wheel on.

@TailWheelsRock Год назад

You know how you get rid of flutter, buy a husky. That’s what I fly there’s two braces on the tail for a reason. That’s the plane of choice if one can afford it.

@sbukosky Год назад

I've never noticed it, but it is concerning. I used to fly a 150 HP Super Cruiser and never noticed such flex. I don't think I'd be wanting to do snap rolls in one with such flutter. I prefer a trim tab over jackscrews.

@FlightChops Год назад

Yeah that’s fair. And I don’t think snap rolls are a thing in stol cubs…

@Anonymous99997 Год назад

Why did you decide to paint the RV? Did the paint add weight?

@ricktoberfest Год назад

The paint will always add weight (just think how much a gallon of paint in a can weighs) but I’m told taking care of bare aluminum is a lot of work compared to a painted plane.

@FlightChops Год назад

The paint on the RV-14 added 34 lbs and moved the CG aft one inch. And keeping it polished was not sustainable for several reasons - mainly that once the vinyl logos were applied, it was impossible to work around them, and you can’t polish over them.

@FlyingNDriving Год назад

No guide wires under the horizontal??

@FlightChops Год назад

Don explains that you can’t have them due to how the trim system works.

@bryanspayde8688 Год назад

Crazy a cpl years ago as a student I had to check out a flight instructor in my jabiru was it legal.. probably not but that’s how it worked

@thatairplaneguy Год назад

Trees don’t break because they can bend.

@shoobidyboop8634 Год назад

For me, I found the guns frequently jammed.

@flyingturtle4313 Год назад

it's normal for modern wing and tail designs to flex and flutter alot. Ever watch the elevator on a modern Boeing or Airbus that's spooling up it's engines on the brakes, that thing is movin' and grovin'.

@telace1 Год назад

Do they make these for the experimental market

@FlightChops Год назад

This is an experimental aircraft, yes.

@easttexan2933 Год назад

well, that looks like a crack about to happen. think I would have to pass on a cub if I were to be in the market for a plane. I really like the Kit Fox like Trent Palmer has.

@doncullen5861 Год назад

I have a Don Wade built Super Cub and it flies Super! It is powerful and responsive. You can’t hardly stall the plane and when it does stall is is very docile. The engineering is there. You can feel it when she flies. I horse it around the pattern g-ing it up in the turns and climbs and I always feel she has more to give. Aerodynamically I think she is a very solid plane. STOL is what she does best. Piper put the engineering in it years ago and all these years later it continues to prove the validity of the design. I LOVE flying my Cub and I thank Don for making me a wonderful plane. Once you get comfortable in a Cub she will steal your heart!

@easttexan2933 Год назад

@@doncullen5861 outstanding !!

@michaeldunlevie9880 Год назад

NOT hearing "yes, we know about this and with that flux there is a life span/hours to inspect". AM hearing you caught this so we have to explain why its there and strong enough/don't be worried... So with that much (yes there's a lot) flutter what is the life span/inspect-replace schedule? Bueller? Bueller?

@FlightChops Год назад

This video was entirely about my responding to viewer feedback on a previous video, pretty dang quickly. Toward the end of this one, I invite further feedback so that I can respond to it in the next one. Your tone here, and reference to a movie joke (that youngsters might not get, regarding a scene with a teacher taking attendance in a class calling the name of a student that isn't there) implies that you don't expect a response; but I really do love that movie, it's an 80's classic for sure...

@michaeldunlevie9880 Год назад

@@FlightChops I did not intend the tone you received, my apology. I meant the silence was from the manufacturer not putting this out there before your discovery and the silence on any life span or inspection time due to the wear by movement of the components (not calling it flutter). Thanks for your videos.

@realulli Год назад

@@michaeldunlevie9880 Did you see the reply from the Cub Crafters (ex-) test pilot? And the other reply from the aerodynamics engineer? It seems this is not flutter, it's just a wobble that seems under control, and a couple of other aircraft do it as well...

@EricMassey748 Год назад

Great video Steve! My carbon cub's h-stab vibrates quite a bit too. Not very noticeable on takeoffs since they don't last very long, but landing behind the power curve in the 40 mph range with some power on you definitely feel the vibration in the stick. Reminds me of this ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-n682zwJwzE4.html

@gregoryhughes Год назад

Look up on youtube "Twin Comanche Flutter" for real aeroelastic flutter. It's a different phenomenon than what's happening with the Super Cubs

@tekanova7480 Год назад

Would beefing up Horiz stab be a wise thing?

@FlightChops Год назад

My understanding, from what Don was saying, is that if you try to take away the movement, you send the forces elsewhere, which might break something else. So in this case, I think the outer parts of the stab flexing when it needs to, stops the inner part where the jack screw and trim mechanism is, from having to take that load..?

@thatguy7085 Год назад

No storms after that Sat storm.

@FlightChops Год назад

Yes, after the initial storm system that those of us who got there early had to survive through, that week was one of the best weather windows ever for Oshkosh that I have experienced; Clear, cool, and not too windy.

@epiren Год назад

So you slip for speed or for altitude, right? I assume you were slipping for speed... Did the cub just want to stay in the air even at that low speed?

@FlightChops Год назад

The slip is to increase the descent rate without increasing speed.

@tbas8741 Год назад

Haha so i was technically right in that its the Propwash causing the tail to Flap & Twist.

@claycassin8437 Год назад

After seeing that footage, I sure as hell am not setting foot in one of those, no matter what the dude says...y'all have fun.

@TRPGpilot Год назад

Were you exposed to elevated levels of tetraethyl lead whist developing within the womb? . . .

@claycassin8437 Год назад

@@TRPGpilot I don't know! Is that what causes one to learn how to recognize "sketchy" when they see it? I also won't get into a majority of hammocks after inspecting the badly rusted eye bolts they are hanging from. It must be the lead. Or maybe it was the asbestos in my schools.

@TRPGpilot Год назад

@@claycassin8437 You sure are clever! Both being a highly distinguished aeronautical engineer and possessing a doctorate in the field of metallurgy. . .

@claycassin8437 Год назад

@@TRPGpilot How did you know? You must be psychic!

@airgliderz Год назад

Unfounded. You are experiencing FEAR, False Ebidence Appearing Real.

@eddycurrent413 Год назад

its greatest strength is its flexibility

@tomstarros3189 Год назад

looks like it is acting like a diving board...and the prop wash is the swimmer...

@FlightChops Год назад

I think this comment wins.

@anmihovil Год назад

How is Flutter generated with three blade prop? I'd like to see that. I wonder is it more or less intense? I assume less.

@monostripezebras Год назад

color me sceptical, regular oscilating bending loads on something so important gonna cause issues in long years from now. I bet.

@craigsanders6925 Год назад

50 year old cubs do the same thing.

@linuxleica Год назад

My cub is built mosty with regular steel serial no is 18-8664 the frame has 19 000 + hours from 1968 tail is still attached :)

@thatguy7085 Год назад

Yikes… fatigue

@PDZ1122 Год назад

Of course the factory people are going to tell you it's alright. It was "engineered that way". That much flex and flutter is not "engineered". It's bad design and they tolerate it because nothing has broken off and killed anyone yet. This is what I can't stand about modern Cub Clones: it's a cheap way for them to produce and sell overpriced and over rated airplanes without having to go through a clean sheet design process. All the shortcomings of the Cub are still there and about they only improvements are more power and wider fuselages. The archaic control system is still there along with that horrible tail design. And they are generally a pain to work on. I'm glad I saw this video; I'm never getting in one again. "It works!" Is no excuse for bad or lazy engineering. But hey, what do you expect for $300,000?

@bigmuz_pilot Год назад

Which plane did you design and build in the hundreds please? How did you solve this issue and maintain a jackscrew for trim? I'd be interested to hear all the details.

@airgliderz Год назад

Not true, You are experiencing FEAR False Evidence Appearing

@earlgreystoke3324 Год назад

The amount of visible flutter of the entire horizontal stabilizer is at best unusual & more likely evidence of a poorly conceived design. The long round stabilizing rod simply fixed at each end is susceptible to vortex shedding which may cause resonant vibrations. The Patriot spokesperson provided a vague, non-engineering answer to a visible problem.

@tnexus13 Год назад

Mike Patey's probably got some knowledge on this with the changes he made to Scrappy? Didn't he swap (or wrap) the wire for a carbon aerofoil?

@earlgreystoke3324 Год назад

@@mzaite Why use a flying, flat zero camber, horizontal stabilizer with jack screw trim in a small two seater aircraft? It is unnecessarily complex & poorly executed. This appears to be a design flaw waiting to fail.

@earlgreystoke3324 Год назад

@@mzaite Good point.

@FlightChops Год назад

Thanks for the insights Michael Zaite - you’ve got it right regarding the trim system. But Don wasn’t blind sided; we’d talked about this early in my flying it (to set my mind at ease when I noticed it) and we decided to do the follow up interview at Osh. Don actually spent probably 5 minute describing the trim system in detail, but I didn’t think it was as relevant for this cut to say anything beyond “the trim system won’t work if the front of the stab is braced”. Don signed off on the fine cut, but I suppose more context here might have helped - it’s hard to keep things tight and also fully informative.

@samscott5230 Год назад

There are very, VERY few people out there more knowledgeable about cubs than Don Wade. His explanation is a reasonable one though maybe not an “engineering” answer. This trim system has been used on Cubs and their many variants since the 1930s. If there were failures due to this design, it would be widely-known by now. Like Don, never have I seen or heard of a failure due to fatigue from flutter.

@peroleable Год назад

Why change things that have worked perfec for many years?

@rogerbee697 Год назад

They didn’t. That was the whole point of this video. Did you not listen to expert?

@craigsanders6925 Год назад

@@rogerbee697 You sure about that?, Cubs go back to 1938.

@rogerbee697 Год назад

@@craigsanders6925 you should be replying to the initial commenter with their question.

@craigsanders6925 Год назад

@@rogerbee697 What didn't work?

@dashriprock2916 Год назад

Sorry I don't like the tail flutter.

@triboarder06 Год назад

@FlightChops the craziness of some peoples comments on your videos and the internet in general is astounding to me. Wish people could just watch and enjoy, keep their mouth shut if they have nothing to contribute in a positive manner. No one is making them watch and most of them probably don't have any experience or knowledge of the subject, just keyboard warriors.

@FlightChops Год назад

Heh, yeah - it is what it is :). The community is largely super positive

@DanFrederiksen Год назад

I'm not particularly a fan of cubs either. It's basically a modern canvas plane. a 100 year old barebones design so I'm not sure why it's a 3-400k$ bird these days. The fluttering tail to me just confirms its basic nature. Why couldn't a stol plane be single piece composite fuselage and single piece wing that didn't need struts or cables.

@ivanmontes2144 Год назад

That’s sketchy

@PDZ1122 Месяц назад

This is what happens when people with little or no real engineering knowledge want to jump on the kit aircraft wagon. They just repackage the same cub-clone components, slap a ridiculous price on it and count on all the wealthy fanboys who don't know any better. Just get a clean sheet of paper and a real engineer to design something better and stop flogging this old design to death. The idea that the kind movement is "built in" and normal is ridiculous. They just don't know any better.

@flytoday Год назад

flying is the quickest way to empty your wallet 😀

@givenfirstnamefamilyfirstn3935 Год назад

It will not be a problem for the original owners.

@Jamesg33 Год назад

I'm sorry, but that amount of movement in a flight control surface is unacceptable under any circumstances. There isn't an aircraft structural engineer or aerodynamicist (I'm both) out there who wouldn't agree with that. I don't know who "Don" is, or what his qualifications are, but his words were not convincing to me. He even admitted to a failure of the support wire and showed you a Band-Aid solution that will just make the failure happen less often, not eliminate it. I'm amazed that so many pilots are okay with brushing this off. We all know the drill. When you bend steel like that back and forth it's like bending an old coat hanger. Eventually, it will break, and the results will not be good. Would you accept that kind of movement on the horizontal of your RV, or any other aircraft you fly? Of course not. That horizontal needs to be re-engineered. And yes, it is possible to stop that movement and still have a trimmable tail surface......

@bobwilson758 Год назад

Disagree tail flutter ok… No no not good - She gonna break .

@bjs2022 Год назад

Please reduce the level of your background music to increase the speech intelligibility.

@rockymountainfly9480 Год назад

I hear him just fine...not even slightly impeded for me. I think the music adds to the energy of the videos.

@clarencewiles963 Год назад

@@rockymountainfly9480 for my hearing aids it’s not so good. Just saying, thanks.

@bjs2022 Год назад

@@rockymountainfly9480 It was the first few minutes when the mix was bad, especially playing at faster than normal speed.

@FlightChops Год назад

Thanks for the feedback, but my cuts are pretty tight and I deliver dialogue fairly fast as I respect people’s time… so if you’re listening at increased speed, that’s got to play a big roll in compromising the clarity of the spoken words.