550 tail failure

[Jamez]

Well it was on its third gently running in lipo packs flight when the tail let go, jammed up on the tail pitch slider, jammed the main gears which stripped and that was it. It's a bit messy, and the tail pitch slider is missing its ball.... that is all I can conclude it has failed there. First flight with the canopy on too... gutted.

Check your balls.....

Anyway the damage is up to about 200 pound. So am thinking salvage the good bits and buy a HK 550 TT for 91 pound and pick it up as they are only 10 miles from me, have a set of 550 nhps, fit them and see how it goes.

I could cry....

[Vortexia]

Ouch ! My sympathy is with you

[RcRotaryMadness]

Love your sig: "I don't crash, I just land with enthusiasm" LOL

Its so annoying when a simple failure leads to an all out crash... feels a bit unfair to be honest...

Was flying a 600 the other day when the tail slider came apart (brass sleeve came out) - instant spiral dive into the deck... luckily not as much damage as yours by the sounds of things... how high up were you at the time?

[bulldog5046]

Having just bought t he 550 I'm interested in a parts list to see what adds up to a £200 crash!?

might be of interest to you, there is a chap selling one on the BMFA site, its also on eBay but he has a spare chassis he was willing to sell for 100 notes but I think it had a little damage....

ive seen reports that the HK 550 kit is no where near the standard of the 450, that's why I bought a trex rather than another HK.

[Jamez]

Will post a complete list but it's canopy, tail gearbox ( it bent where it jammed), shafts, boom, torque tube gears, some linkages, blades ( main and tail ), boom supports, tail pitch rod, tail pitch arm, maybe the slider and tail blade grips... that's without stripping, and checking

[coolice]

Hey.

Sorry to hear of your problem and a repair bill on a new model.

Is it possible that you could post up some picturea of the failure at all, specifically the tail gearbox where it locked up? A picture tells a thousand words and I'm interested to understand just what failed.
.

[johnsandywhite]

Just a point on the HK550. I bought one as a spare airframe. The frame itself feels really good and solid. The problem is that there are very slight differences between it and the Trex 550. So if in future you were to buy or fit a Trex torque tube and tail boom there is a matter of a good enough alignment from the main/tail gears and the torque tube gears. In time, the mesh will wear and the tail will strip and let go. If you use it complete with the belt drive tail, then make sure that the tail boom is locked and cannot move. Otherwise you will loose the tail AGAIN.

[Jamez]

Basically the ball has come out of the pitch slider....tail pitch control lost, the gyro then wound the pitch arm as far as it could go, this fouled on a tail blade grip, bending the mounting point, locking the tail and drive gears, stripping the Main gear. Maybe post a pic later. Am at work so can't now.

[NoFixedAbode]

Re: 550 tail failure

You say it is a new build. Did you rebuild the factory build?

[Jamez]

Yep....don't trust align as far as I can throw them...

[GIXERMAN]

Sounds like a maintenance issue to me, no thread lock on ball or has the ball sheared off.

[xygax]

Just get a fusion and put short blades on it... will be fine...

[MarkG_R1]

Lack of threadlock?

[squeaky pete]

i know of a banging fusion for sale.......

[Mark Chaplin]

The op said the pitch slider ball was missing. If this did indeed happen during flight setting the limit would have no effect as there was/is nothing to stop the tail blade grips doing as they please.
Its always a problem fault finding the cause of the crash after the event.
Hope you get it sorted soon and back in the air.