Kalinin K-7

1933

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Kalinin K-7

Designed by World War I aviator Konstantin Kalinin with a wingspan greater than a B-52's and a much greater wing area, the K-7 was one of the biggest aircraft built before the jet age. It was only one engine short of the B-52 as well, having the curious arrangement of six pulling on the wing leading edge and one pushing at the rear.

The K-7's very brief first flight showed up instability and serious vibration caused by the airframe resonating with the engine frequency. The solution to this 'flutter' was thought to be to shorten and strengthen the tail booms, little being known then about the natural frequencies of structures and their response to vibration. On the 11th flight, during a speed test, the port tailboom vibrated, fractured, jammed the elevator and caused the giant aircraft to plough into the ground, killing 15.

Undaunted by this disaster, Kalinin's team began construction of two further K-7s in a new factory, but the vicissitudes of Stalin's Russia saw the project abandoned, and in 1938 the arrest and execution of Kalinin on trumped up espionage and sabotage charges.

Jim Winchester "The World's Worst Aircraft", 2005

FACTS AND FIGURES

© The K-7 was one of the first metal aircraft with a twin-boom layout.

© As originally designed the K-7 was to have engines in the undercarriage sponsons. As completed the bomber had gun positions, the bomb load and an internal staircase as well as two large wheels in each massive sponson.

© The K-7's control surfaces were all deflected by the use of large trim tab surfaces mounted on struts.

© The K-7 was said to have had a pilot, 18 crew members and one passenger when it crashed, killing all but five crew. It is not clear what they all did, but no doubt tending to the engines was a full-time task.

Kalinin K-7 on YOUTUBE

3-View 
Kalinin K-7A three-view drawing (800 x 964)

Specification 
 CREW12
 PASSENGERS128
 ENGINE7 x M34F, 550kW
 WEIGHTS
  Take-off weight38000 kg83776 lb
  Empty weight24400 kg53793 lb
 DIMENSIONS
  Wingspan53.0 m174 ft 11 in
  Length28.0 m92 ft 10 in
  Wing area454.0 m24886.81 sq ft
 PERFORMANCE
  Max. speed234 km/h145 mph
  Cruise speed180 km/h112 mph
  Ceiling4000 m13100 ft
  Range3030 km1883 miles

Comments1-20 21-40
dave, e-mail, 12.03.2012 02:28

the soviets built this plane just in case they had to take on chuck norris.

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lxbfYeaa, e-mail, 14.03.2024 dave

20

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Mr R. Braga, e-mail, 07.11.2011 23:14

Looks like something out of H.G.Well's "War of the Worlds"
or the illustrative aerial creations by Bruce Mccall's "Zany Afternoons". I have no doubts this aircraft could have flown (minus the cannons) eventually with all its faults ironed out. Probably best flown with the pilots and crew wearing brown corduroy trousers. What a sight it would have made at air shows.

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derselblat, e-mail, 05.08.2011 07:19

See, Mel, I think that's the point these other guys were making: those pix are fake. They're hilarious, but totally fictional.

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mark, e-mail, 01.05.2011 00:18

I seen the bogus pictures of this airplane, they look like something from the science fiction movie "Wings Over The World"

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yakov smirnoff, 26.04.2011 07:06

In Russia, the planes execute you...

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a.machiaverna, e-mail, 09.04.2011 05:32

"Uncle Joe" Stalin had a very poor sense of humor! Violent man.

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Bill Warner, e-mail, 17.12.2010 10:15

What a "fun" project! Maybe Kalinin missed the engineering class where they discussed Newton's third law? I think the cannon may have come off the Potemkin.

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Ian, e-mail, 02.11.2010 22:56

There needs to be some accurate dimentions on this. I've seen it vary through several pages.

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Graeme, e-mail, 30.03.2010 01:49

Why are there all sorts of fake images of the K-7 if you Google it?!?

Too bad the real one crashed - during a high speed test, one of the tailbooms fluttered, jammed the elevator, and kept the aircraft in the dive. 15 died.

If you like this aircraft, check out the Tupolev ANT-20 Maxim Gorki - the ultimate propaganda machine!

Thank you,

Graeme

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Marv, e-mail, 27.03.2010 22:55

Too bad Konstntin Kalinin could not have defected to the West B4 Stalin had him off'ed. Look at the contributions Mr. Sikorski made to air flight in his lifetime.

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jimmy neutron, e-mail, 01.02.2010 16:29

it has wrong engine duh!!!! lol hi peace

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Patsy Elders, e-mail, 29.01.2010 03:27

Thanks guys for the heads up. I just received the picture of the fake one. Looks awesome, but it is not real.

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George Silberbauer, e-mail, 05.01.2010 02:08

If all those guns were fired at the same time the poor old dear would snap into a really spectacular stall, despite the momentum of those 38000-odd kgs. (It could get tricky even on a Spitfire Mk XII and only 8 .303's if you didn't have enough on the ASI.)Mind you, with that very low aspect-ratio wing, she may simply have mushed and wallowed horribly.

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Trevor de Varyer, Australia, 31.10.2009 14:58

It is interesting that in Bill Gunston's book "Back to the Drawing Board", there is aa photo of a full scale mock-up with a different engine arrangement of the completed example. It is photographed with the same background as one of the photos of the completed aircraft.

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William Robison, e-mail, 16.09.2009 07:22

Why aren't there photos of it in flight?? I wonder if it
actually ever got airborne....

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tom friedman, e-mail, 10.09.2009 06:28

if it's ugly & boxy it's either russian or french!!

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Mac, e-mail, 13.06.2009 23:46

Sorry, a B-52s wingspan was 185 feet, which is 11 feet, one inch longer than the K-7s. Trust me, I piloted B-52s for nearly nine years.

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OH Minto, e-mail, 05.05.2009 22:18

I found some nice pictures of it. It's beautiful I would I could live in one.
englishrussia.com /?p=2231

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jeff, e-mail, 30.04.2009 19:13

clearly no canons like battle ships according to these pictures

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Tomas K. Hoiaas, e-mail, 07.04.2009 02:06

Hi, Folks !!
A fev days ago I got an E-mail from a Norwegian friend,showing a BIG Kalinin K-7.Somewhere later I read something saying;"This aircraft is not the real K-7".Could you tell me if this is right ? Greatings from: Tom in Brazil.....

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1-20 21-40

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