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Russian KA-52 [Black Shark, NATO : Hokum] vibration issues seen in videos.

Russian KA-52 [Black Shark, NATO : Hokum] vibration issues seen in videos.

Russian KA-52 [Black Shark, NATO : Hokum] vibration issues seen in videos.

(OP)
I had to see the videos to actually comprehend what was being reported.

Unbelievable. NO UNTHINKABLE! The 'shaking/flapping' appears to be linked with wings weapons loads. The flapping appears persistent thru most of the low speed range, so releasing free-flight ordnance must be a 'crap-shoot'.

Russia’s Ka-52 Attack Helicopters Have A Serious Vibration Problem
Videos show significant vibration on heavily laden Ka-52 Hokum attack helicopters and experts don’t like what they see.

Russian Ka-52 Hokum attack helicopters fighting in the war in Ukraine are suffering from a major vibration issue that could, according to at least one expert The War Zone consulted, decrease reliability and, potentially, be unsafe. At best, according to assessments we’ve received, the vibration is likely to reduce the efficiency of the weapons these helicopters carry, and may also restrict weapon life. In turn, this could have an effect on the capability of the Ka-52, one of the most widely used Russian helicopters of the conflict so far.

Video clips showing Ka-52s operating with their stub wings rapidly bouncing up and down began to appear on social media in recent weeks and there has already been speculation that the issue could lead to “mechanical failures and vibration-induced fatigue.”


https://www.thedrive.com/the-war-zone/russias-ka-5...

"Some fear flutter because they do not understand it. And some fear it because they do." --Theodore von Karman, aerodynamicist

Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

RE: Russian KA-52 [Black Shark, NATO : Hokum] vibration issues seen in videos.

(OP)
IR... Did the Apache have this gun vibration during R&D... and was it eliminated/marginalized [IE: restricted angle of fire, restricted burst duration, changed the rate-of fire, etc, etc]... or is it still present and considered 'transient enough' to be acceptable? I know that the Army would be exceptionally cautious about adverse conditions, like this.

Inconceivable that this relatively 'steady-state' wing-ordnance vibration condition could exist in an operational aircraft... unless of course, all possible external ordnance was not fully vetted prior to combat. I wonder if the Russians engineers considered this NOT a significant issue and signed-off [or NOT] on-it.

US R&D flight testing is exhaustive/repetitive. Every conceivable ordnance combination is tested/vetted for every typical flight/fight condition [G, CG, aero, gun, etc]... including intentional jettison. Some crazy and dangerous incidents have happened, and been-resolved or restricted, as a result of R&D flights.

EXAMPLE. The prototype A-10, during R&D testing of the [GAU-8] gun, exhibited severe gun-gas-exhaust flow into the engines. This situation caused a double-engine flame-out on a test aircraft that was non-recoverable [crash video is on YouTube]. The condition was corrected [mostly] by internal gun-bay gas-path venting changes... and the use of inboard LE slats that extend for gun-firing to re-rout external gun gases [flowing over the wing-root] below the engine inlets. This was a MANDATORY/flight-critical mod.

Personal NOTE. When I left the far PACAF [return home to CONUS], an A-10 squadron I'd worked with extensively, presented me with a polished-up dummy GAU-8 Round. It is HUGE!

Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

RE: Russian KA-52 [Black Shark, NATO : Hokum] vibration issues seen in videos.

Quote:

IR... Did the Apache have this gun vibration during R&D... and was it eliminated/marginalized [IE: restricted angle of fire, restricted burst duration, changed the rate-of fire, etc, etc]... or is it still present and considered 'transient enough' to be acceptable? I know that the Army would be exceptionally cautious about adverse conditions, like this.

I don't recall the specifics, but I do seem to remember that it got to "60 Minutes" so it made it into production shipsets. There was supposedly a production retrofit mod that fixed, or minimized the problem, but I'm admittedly a bit hazy as to the timing and details. The issue was primarily when firing to the side, since the rotational inertial was worse and couldn't compensate for the input from the gun recoil.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
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