Big Props KC-97 Stratotanker

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6 жыл бұрын

This video is about the KC-97 Stratotanker.
Toward the end of World War II, Boeing developed the Model 367, a military transport based on the B-29 bomber. Its civilian counterpart was the Model 377 Stratocruiser. Designated the C-97, it had a double-lobe fuselage consisting of two intersecting circular sections, so that the 74-foot-long (23-meter-long) upper deck had a larger diameter. Cargo was loaded through large clamshell-type doors in the belly of the aircraft using a built-in ramp and a hoist. Its wings, engine gear and other parts were similar to the B-29.
In January 1945, an XC-97, piloted by Maj. Curtin L. Reinhardt, set a transport speed record by flying 383 mph (617 kph) between Seattle, Wash., and Washington, D.C., with 20,000 pounds (9072 kilograms) of cargo. The production version that flew in June 1949 had outboard wing fuel tanks to increase its range.
During the Korean War, C-97s were used to evacuate casualties. Others became flying command posts for Strategic Air Command (SAC) personnel. The C-97 was designated KC-97 when it was equipped with the Boeing-designed flying boom for aerial refueling - the boom had controls
so the boom operator or “boomer” could literally "fly" the end of the boom from the KC-97 aerial tanker into the receiving airplane.
There were 888 C-97s built between 1947 and 1958. Of those, 219 were adapted as KC-97E and F tankers and 592 were KC-97G models. The KC-97Gs had additional 700-gallon (2650-liter) external fuel tanks under each wing and could dispense 8,513 gallons (32,225 liters) of fuel while carrying 96 troops.
Sales of the KC-97s helped pull Boeing out of the postwar slump, and because they extended the range of bombers and fighters, the KC-97 tankers became crucial to SAC operations.
Technical Specifications
C-97 Stratofreighter
First flight Nov. 9, 1944
Model number 367
Classification Military transport
Span 141 feet 3 inches
Length 117 feet 5 inches (including boom)
Gross weight 175,000 pounds
Top speed 375 mph
Cruising speed 300 mph
Range 4,300 miles
Ceiling 35,000 feet
Power Four 3,500-horsepower P&W Wasp major engines
Accommodation
4 crew, 96 troops or 69 stretchers, tanker equipment

Пікірлер: 92

@orangejuicejones6075 4 жыл бұрын

My father flew a KC-97 out of Offutt AFB I believe. In the early 1990s I was working at the Florence Morning News (S.C.) as a 20 something cub reporter. Well Florence at the time had a dusty "Air Museum" featuring a KC-97 that had seen better days. I surprised my dad with a trip to see it when he came to visit one summer. The look on his face when we drove up to the plane will stay with me forever. Once the curator heard our story, he allowed my dad to board and enter the cockpit. He couldn't have been happier despite the cobwebs and torn seats. We hung out for a bit and he rehashed old stories of this magnificent bird. Great day. RIP pops! Thanks for the video

@ginger9702 3 жыл бұрын

My father was a radio operator and flew out of Roswell AFB. He perished in a mishap in Gray Mountain, AZ in 1957. I can imagine the tour was special for your pops.

@jonbryn4 4 жыл бұрын

Wow, my dad ,Lt.Col. john cornelius, flew those for a living and was awarded an air force commendation medal for his paticipation in the cuban missile crisis, great videa thnks

@Dr.Pepper001 Жыл бұрын

My uncle was on-board a KC-97 as a crewman and the aircraft crashed, killing everyone on-board (of course). I'm 76 now but was a kid when it happened. The Air Force couldn't recover enough of his remains for the family to bury, so there is a marker headstone in our family plot.

@zacktong8105 2 жыл бұрын

In a week or so I'll be attending a social gathering of family and friends of Bob, a neighbor who passed away at 87 a year ago who had been a co-pilot at Dow AFB, Bangor Me in the Fifties. But a year or so earlier I had shown him the Hagerstown C-97 video of probably the last one still flying and he pointed out the does and DON'TS of operating one which required strict adherence. By the mid Sixties when I served they were mostly gone except for the Guard KCs. We used to see them at Lajes AB, Azores in '68 and early '69 until suddenly they vanished as too costly for overseas use and youngster mechanics jet trained at Chanute had no idea how to work on them. I never actually got to fly on one though I did a KC-135 as an ROTC cadet at summer camp. I offered to say a few words about what a challenge it must have been to fly one of these, but his widow doesn't want it. So I'll say it here in tribute. "You are not forgotten."

@AS-zk6hz 5 жыл бұрын

Was a passenger on one of these when our c119 broke down. The national guard flew these out of oHare reserve military base. They gave us a lift back to the base where were with the 928th combat support squadron. All that high octane fuel under us made me nervous. The guard unit I understand was quite proficient in their duties.

@markdayneowalla 5 жыл бұрын

My father flew these and refueled mostly B-47s in the 50's-early 60's before moving to rescue. Then he flew the HC-97 for a bit before flying the HC-130 Hercules. I have some 8mm footage that he shot of refueling that I need to upload.

@ginger9702 3 жыл бұрын

My dad was a radio operator on the KC-97 and was stationed at Roswell in the early 50's.

@andrewmeadows3232 Жыл бұрын

@@ginger9702 Nice both of you. My dad began his USAF career piloting B-25s and moved to KC-97s. Ended up flying DC-10s and then 747s for United. Always a big bird guy lol Said he felt he was about to land a Cessna from 40 feet up. These youtube videos bring me back so thanks for posting.

@ditto1958 2 жыл бұрын

When I was in high school in the 70’s my friend was planning to be a commercial pilot. I remember going with him to an Air Force National Guard facility where they had a KC-97 simulator. My friend would actually fly it and do simulated refueling missions. Cool plane.

@seandalton2580 11 ай бұрын

I got a kick out of the beginning of the US military promo film where they mention the automatic entrance and if you look at the left side of the door frame you can see someone inside cranking up the door! 🤣

@timmayer8723 5 жыл бұрын

I spent five years as a mechanic with the 146th air transport squadron based at Van Nuys California these were called MATS squadrons at one time. We flew the cargo version of the C-97 G and H models which all had P&W R-4360 radials. We were the long haul 18 wheelers of the sky's in the South Pacific. If you could get the cargo in the rear clam shell ramp and tie it down, the C-97 would take if across the Pacific. We flew ten flights a week to Hawaii with about twenty aircraft and on to Tan Son Nuit air base in Viet Nam. We took soilders to Nam and brought them back, plus all their equipment. Also many ordinance flights to the Canal Zone which was a way point for munitions during the Nam war. The plane was smooth, powerful and easy to fly. A number of our pilots were F-86 pilots durning the Korean War and transitioned over to the C-97. Our sister wing in Phoenix Arizona was strictly air refueling. One interesting aside, the war time radios were powerful enough to radio check Hickim air base in ha

@eutimiochavez415 Ай бұрын

The flight engineer had more work to do then he pilot and co pilot ❤❤❤

@JamesWeatherly 6 жыл бұрын

From Wyatt M - Just watched the video. Bravo! Very good. Some inside info. The KC-97 usually flew with a crew of 6. The pilot, co-pilot, engineer, boom operator, crew chief & assistant crew chief if the plane was flying any length of time or distance. The boom operator doubled as a steward. (Non-Comm) After takeoff, he'd fire up the built-in coffee pot & break out the sandwiches made by the mess hall. The toilet was nothing more than a closet with a honeypot which was a fancy name for bucket emptied after every flight. I was an assistant crew chief & flew many happy hours in the KC-97 & was part of more than a few in-flight refueling missions. A very steady, reliable airplane. An amazing experience. Looking forward to your next segment in the series.

@JamesWeatherly 6 жыл бұрын

Wyatt thanks for your service and great feedback

@williamloh9018 3 жыл бұрын

My Dad flew these at MacDill when I was born...the B-29 was a trainer for him. Then he transitioned into the KC-135 at Castle and we went to McCoy. He went to Guam twice and also flew the B-52...in combat. And then never mentioned any of it. He didn't do it for that... He did it for you. Then he got Parkinson's from the Agent Orange, and the VA asked him to prove that he was on the ground in Vietnam before they would cover his care. My Mom had somehow thrown out his logbooks, and they've had a convenient fire at Maxwell which destroyed the records. His commander told me he had sent my father there himself many times, and he had been dealing with similar requests for many years. It did not help. He said they never thought they would need to prove anything to the same people who had ordered them to go there and do these things. Then the government had a Twilight Zone gatekeeper department to help stop them from doing the right thing. So very sad... My Dad did his duty and did the right thing as a matter of policy. Now we've spent so much government money on silly things that don't work well enough...and bailed out the Hamptons & Co. in 2009. While my Dad got hosed out of his life savings...not that it paid very well for him to risk his life for 21 years. At least he was not here to see the ignorant traitor cult run amok like barnyard animals on 6 January. Parkinson's was awful though...he did not deserve that either.

@james4582 2 жыл бұрын

That’s sad that it happened that way. Your dad certainly deserved better. I was at Castle 64 to 67 KC 135 ground crew

@williamloh9018 2 жыл бұрын

@@james4582 Thank you Sir...and he did. They all did. The truth is pretty ugly sometimes...and The Nam was just a money pump like the Afghan one. Take care...

@kc97chief 2 жыл бұрын

Crew Chief on a KC97 for 3 years at Pease AFB 59-62 . Learned a lot.

@reedofurantia606 2 жыл бұрын

Boomer here 509th and 100th

@christinadaly7743 5 жыл бұрын

Rick Daly says; I was lucky enough to take a hop from Goose Bay Labrador to Pease AFB , it was VFR all the way in beautiful weather and the 97's last flight . As I remember , the Engineer was smoking a pipe and the Pilot smoked cigarettes with the side window half open . It was " shaky " and very noisy and upon landing in New Hampshire , the breaks howled and squealed as we taxied to Base Ops . That was 1971 and later that year , we got a real treat to see " Enola Gay " taxi in and park , it took off the next day forever gone ! just as our " Strategic Air Command " did . Thanks for the memories JTW

@daviddunsmore103 4 жыл бұрын

Are you saying that the Enola Gay was still flying around in 1971? Please tell us more, like who was operating it and what they were doing with it? I love learning new things, thanks!

@PrismRisen 3 жыл бұрын

Excellent integration of components, models, and specs. Top notch!

@n6mz 4 жыл бұрын

Holy cow, I never realized that the early test models had R-3350s instead of Pratt corncobs (which are 4 rows of 7 cylinders, not 4 rows of 9). "Learn something new every day." Great channel, THANKS. BTW, round-engine geeks should find copies of Graham White's books on the R-2800 and R-4360, they're outstanding. Also, the guy showing the J-47 is AgentJayZ who owns a gas turbine repair company, his youtube videos are outstanding. Keep up the good work.

@eugeneoreilly9356 11 ай бұрын

White's books are very technical.

@jeffreyplum5259 Жыл бұрын

I remember going to Bangor-Brewster International Airport as a kid. It had F-101 Voodoos on alert, during the cold war. My uncle was an Air Guard mechanic on them. It was at the end pf the Vietnam War, so the KC-97 were long gone. The hanger doors still had inner doors shaped to fit arounf the tails of C-97 aircraft. They could work on the C-97 in the hanger with its tail outside. This was a nice feature during a Maine winter, I can tell you. My uncle was Army Air Corp during World War 2, then Air Force then full time Air National Guard. I am proud of his lifetime of service Thanks for reminding me of that once in a lifetime visit. God Bless all who Serve.

@larryreece1427 5 жыл бұрын

The reason they hung two jet engines on it because when fueling the b 52 it wasnt fast enough the b 52 just about stalled while recieving fuel because the kg 97 was so slow

@andrewmeadows3232 Жыл бұрын

My father flew KC-97s. One of my favorite memories is surprising him at the Florence Air Museum in South Carolina with a dusty KC. I think the museum has since closed - not much action in Florience lol - but my dad was so grateful he tipped the "curator" alot. Bought me a steak dinner to boot! RIP pops

@Code3forever 2 жыл бұрын

In the middle 50s, I flew with my Dad on United from LA to Honolulu on the Stratocruiser and it was amazing. My old partner flew medevac from Vietnam to Honolulu and Van Nuys with the California Air National Guard on weekends with some Major who was a radio personality on LA radio. They were all reserves. Some of their trips went via Elmendorf afb in Alaska. He also flew in the C-141 during the 60s.

@magicpencil6995 3 жыл бұрын

Whe I was a kid, I remember these KC-97s flying around Knoxville, TN - loved seeing them!!

@timmayer8723 5 жыл бұрын

I flew many missions in the C-97. Because of the location of the entry/exit door the engines were started in this order 4-3-1-2 . If started in the usual manner which would be 1-2 port 3-4 starboard, #2 engine running would block the exit should some problem occur that called for the evacuation of all on board. Ours were cargo 97s which had a very large out swinging cargo door on the starboard second level of the aircraft, just forward of the # 3 propellor. Once #3 engine was started this door couldn't be used for escape from the aircraft. There was a 4' y 3' escape hatch aft of the engines over the wings and of course there was a very large double electrically operated clam shell door mechanism through which 99% of the load was passed into the aircraft. Because our missions during the Vietnam Nam war were over the Pacific to Hickam Air Force base and continuing on to Tan Son Nuit Viet Nam we had ten man oceanic inflatable rafts, usually one was sufficient but if the plane was returning from Nam with R&R troops we used two of the very large inflatables. It was a very reliable aircraft so crossing the Pacific Ocean was not an issue, a distance of about 6000 nautical miles, one way. We flew at about 280 IAS at 8000 MSL.

@flyingfortressrc1794 Жыл бұрын

Great video. Thanks.

@jerryjustice8803 3 жыл бұрын

I flew in one from SAC headquarters in California to South Dakota in 1971. It was quite an airplane and pretty big.

@aztcgreg 6 жыл бұрын

Nice video

@JamesWeatherly 6 жыл бұрын

Thanks! Keeping watching. James

@edricklawrenceong7776 3 жыл бұрын

That fuselage looks like it has the aerodynamic qualities of a brick.

@davidkosh1058 3 жыл бұрын

My dad was a crew chief on this plane. He loved being in the air with those big 4360's purring. He always said it came along late which made fueling jets a challenge. They had to run at max power while the jets would almost be at a stall. Still loved it. It is such a cool looking machine.

@an-zm4xg 2 жыл бұрын

Do you have a walk around the Convair B-36 Peacemaker? Wonderful video, sir.

@RallyRat 4 жыл бұрын

Shout out to AgentJayZ for that J47 clip. One of my favorite channels on KZfaq!

@chrispeters4405 2 жыл бұрын

love that plane, so hard to find good pictures...

@sevenpointsixtwo9707 3 жыл бұрын

There’s a static display at Malmstrom AFB. She’s a beast!

@johnmoore1290 2 жыл бұрын

Back around 1980 Hawkins and Powers Aviation in Greybull,Wy. was refurbing some C-97's to fly freight in the Middle-East. I don't know if they ever made it there or not.

@donaldstanfield8862 4 жыл бұрын

Must have had great a/c to cool that cockpit w so much glass area!

@kareyriggs1018 3 жыл бұрын

Wow at NAS Dallas there were dozens of these tankers back in the 60s

@reedofurantia606 2 жыл бұрын

I remember well the '97 G's ... flew in the 509th AREFS at Pease AFB 61-65

@captainclone1367 3 жыл бұрын

The initial C-97 was power with the Wright R-3350, like the B-29 was!! The later KC-97's and the B-50's used the P&W 4360 turbo compound engines!

@garyacker7388 3 жыл бұрын

I got to sit in the jump seat in one coming home from Ft Sill to Hill Airforce Base. 1970

@jeffwalther3935 3 жыл бұрын

The sheer metaphorical meaning, the aviation "poetry" and poetic BEAUTY of the massively-powered KC-97 going at full-cruise, boom aerially-refueling a, full-flapped, dive-braked gear-extended, nose-high B-47, engines smokin' probably, barely 20-50 knots above stall speed, at 20,000 feet is engraved on the hearts of anyone who knows and loves (military) aircraft. It is the BEST "missing link" image between propeller and jet to beings who make things like propellers, jets, aircraft and such, like no one or nothing we know of else, for sure. It is then, a demonstration and marker of technological evolutionary development, (glorious and pitiful) that is as deep as I can imagine in importance to recognize as such. It is entirely wonderful.

@andrewmeadows3232 Жыл бұрын

My dad had to emergency land in the Canary Islands in a KC-97 on two engines. Couldn't light a cigarette his hands were shaking so badly. He said they worked the shit out of those planes.

@jeffwalther3935 Жыл бұрын

@@andrewmeadows3232 The only reason the KC-97 was ssooo "Worked the shit out . . ." wuz because they weren't designed to refuel jet bombers like the B-47, who really needed 3-4 refuelings apiece to accomplish their high speed intercontinental strike AND return safely to base or land. The B-47 was so necessarily aerodynamically slick and had gas guzzlin' smoky, relatively inefficient (first generation) engines, that when refueling from the KC-97, the propeller-driven Stratotankers were at full throttle, takeoff speed, just a few dozen knots above the B-47's stall speed, SSSOO the wunderweapon of its time, B-47 Stratojet had to even deploy its flaps and landing gear AND add some power to cruise stably enough to take on fuel at all; all done day and night in the largest propwash mess you can imagine. Colossal planet-scale target requirements range made aerial refueling a CREDIBLE strategic weapon (B-47's as a matter of course) the Stratotanker filling in in the '50's until Boeing came along with KC-135's patterned after the iconic Boeing 707 that made aerial refueling reliable and safe as it is today. Aerial refueling is nearly-miraculous AND - a linchpin to our entire aerial war plans today; real testament to superior American airmanship, imho.

@davef.2811 2 жыл бұрын

Where are all these planes parked in this video? @ 5:28, a B-23 Dragon is seen in the background, that's very rare!

@firstielasty1162 Жыл бұрын

What is the music at the end? I like it. The kc97L is cool, also. I think the "L" means j47's. I think that they (the jets) were run on the 115/145 avgas rather than adding jet fuel. Slightly less power, and probably some fouling from all the tetraethyl lead. I read that the r4360/propeller combination was troublesome. There is a sometimes airworthy c-97 stuck at an airport near me with engine trouble. I would love to see it fly again, they are working on it. I imagine finding usable parts is challenging, hope they don't take dumb risks due to being too passionate about making it fly again. It's not a harmless antique tractor, but a very complex high performance (in its own way) machine that had a less than stellar record when maintained with cubic dollars, and crewed by constantly trained pilots, and engineers. And support from Boeing, Pratt & Whitney, Hamilton Standard, etc. Who now would want nothing to do with it. Just an oil change and plug cleaning is very significant labor and expense for a few guys. Probably more than 100 gallons per engine...the b36 with 4360s had a 190 gal. tank for each engine. Operating one of these isn't really a "hobby". Nevertheless..I hope to see it fly!

@terrygunn6723 5 жыл бұрын

JP 4 oil and ADI first aircraft refueler

@timmayer8723 4 жыл бұрын

JTW made a mistake in their narrative on the number of cylinders on the 4360. The engines are four rows of seven cylinders (28) not nine cylinders (36).

@JamesWeatherly 4 жыл бұрын

This has been corrected. Thanks for all who commented on this. My A&P instructor from 40 years back would not be very please with that mistake. :(

@timmayer8723 4 жыл бұрын

I got my A&P license in 1962. I made $3.50 an hour. Never did like safety wiring or pulling inspection plates.

@JamesWeatherly 4 жыл бұрын

My new remastered HD version of "The High Price of Freedom" is available for you to enjoy - kzfaq.info/get/bejne/feCAaZugvLaxZYk.html

@edwardyork4321 5 жыл бұрын

GREAT VID 👍 Can you tell us where the museum video was shot?? Would LOVE to take my Grands to see it 😉

@LenLamberg 4 жыл бұрын

I believe this is the Castle Air Museum in Atwater California, near San Jose.

@JamesWeatherly 4 жыл бұрын

@@LenLamberg That is correct Castle Air Museum

@edwardyork4321 4 жыл бұрын

Thanks 👍

@55hemidodge 6 жыл бұрын

The R4360 consisted of 4 rows of 7 cylinders = 28 cylinders not 4 rows of 9 as the narrator stated, good video though

@JamesWeatherly 6 жыл бұрын

Great catch. My bad. Yes 4 rows with 7 cylinders. Thanks and keep watching. James

@mjw1955 5 жыл бұрын

As an interesting aside, Continental experimented with and engine that DID have 36 cylinders; four rows of 9 cylinders each. They had air cooled cylinders but liquid cooled heads. The prop shaft had an SAE-90 spline!

@joerosenberry269 4 жыл бұрын

I worked 0n WB50s on Guam an in Japan, an they had the 4350 engines also They tracked storms in the Pacific, an helped make weather forecast for the area !!!!!

@stephaniebooth6169 5 жыл бұрын

This aircraft was also used by airlines

@thunderbird1921 4 жыл бұрын

I'm pretty sure this plane appears in the film Strategic Air Command starring Jimmy Stewart. If I remember correctly, it was shown refueling a flight of B-47 Stratojets. Great video of a remarkable plane.

@pedromunoz2225 3 жыл бұрын

Este avión estuvo en servicio en la Fuerza Aérea de España.

@jonbryn4 6 жыл бұрын

The orinial model, obiously, was equipped with r-2800s

@luvr381 6 жыл бұрын

No, Wright R-3350s.

@55hemidodge 6 жыл бұрын

The YC-97A had R3350s same as the B-29

@teenagerinsac 4 жыл бұрын

@@55hemidodge and the shorter tail of a 29 too

@tallersimon 2 жыл бұрын

Had to turn off after the 4th wow!

@eutimiochavez415 3 жыл бұрын

In 1944 it was called the army air core

@eutimiochavez415 3 жыл бұрын

No sir it was 1947 I was a flight engineer on a kc97 when I was in the Air Force thank u for ur service sir.

@ginger9702 3 жыл бұрын

@@eutimiochavez415 Where were you stationed in the Air Force? What year were you the flight engineer?

@eutimiochavez415 Ай бұрын

Yea but it was better time to fly an airplane?❤❤❤

@deannewhart2183 4 жыл бұрын

It looks like a odd B 29

@JamesWeatherly 4 жыл бұрын

The plane was a modified B29 airframe.

@deannewhart2183 4 жыл бұрын

@@JamesWeatherly I thought so

@AviationAtWar 4 жыл бұрын

Credit for my video clip would be nice.

@JamesWeatherly 4 жыл бұрын

Let my know the point in the video and I will be glad to place a credit.

@AviationAtWar 4 жыл бұрын

@@JamesWeatherly 5:44-6:30.

@AndrewMurphy8383 4 жыл бұрын

in 1944 they was not called us army airforce they was called us army air something

@RonOhio 3 жыл бұрын

Army Air Corps

@apolloniaaskew9487 3 жыл бұрын

There's some jobs that using remote control technology CAN'T do and refueling aircraft by cameras isn't one of them. A human boom operator is the ONLY way to refuel in flight. The KC-46 boom operator sits in the cockpit and refuel remotely.

@StaceyV51 5 жыл бұрын

It's 4 rows of 7 cylinders not 9. Great Video though!

@JamesWeatherly 4 жыл бұрын

Correct my bad - en.wikipedia.org/wiki/Pratt_%26_Whitney_R-4360_Wasp_Major

@StaceyV51 4 жыл бұрын

@@JamesWeatherly All good man! love the channel! I see the R2800s everyday we have some surplus/ as removed. I wish we had one of these beasts in person!

@jeffwalther3935 3 жыл бұрын

Who can't see B-29 in the KC-97?! The entire KC-97 is B-29 redesigned with all those features, even the nose! for high altitude, heavy-lift military transport, as is the Stratoliner? then a modification of a B-29 as a first double decker luxury, passenger Stratoliner, the jumbo jet of its day, with the same stunning overwhelming size (and sound), nose and tail, of it's day too! But there's a goldmine in the history and heritage and wonder of the peerless J-47 engine and it's (mis)adventures in the early Cold War AAF-USAF story that is firmly held by that special engine alone. And the KC-97 has a wonderful dual-role with THIS engine too. Together they FIRST developed, from near scratch, at breakneck speed, every bit of practical, reliable aerial refueling.

@jimfling2128 4 жыл бұрын

A failure of a tanker. Only marginally better the KB-50 it replaced. Refueling a B-47 would require descending to 20,000 feet and to gain speed go into a shallow dive to maintain enough speed for hook up. Then the B-47 would have to climb back from 15,000 feet to cruise at 40,000 burning off a lot of the fuel it just got. Also the beast had a nasty habit of loosing propellers. Sometimes the loss of #3 would take out #4 or 2 would take out #1 causing a crash. If the prop came off toward the fuselage it was right in line with the navigator & radio operator and make for a really bad day. Altogether not a good ride.

@eugeneoreilly9356 11 ай бұрын

The engine was prone to sudden seizure when the spinning propeller inertia would then shear the gears leaving a runaway propeller which couldn't be feathered.Several accidents happened.