450 Not My Week

[RMB677]

After having a crash with my modified HBK4 I changed over to flying my Blade 450 3D. All was well yesterday till I started getting occasional CCW spinning. A visual check and test of control responses showed nothing. This morning I decided to fly it, took off, got about 3' off the ground and it started spinning, couldn't get any rudder response and crashed into a concrete planter on the patio.

Results: pair of FRP blades smashed, broken blade holder, bent feathering shaft. As I went further into the investigation I noted that eventhough the tail belt tension was good the belt was slipping. Tore down the tail boom and noted the belt worn in spots but even stranger saw that the belt gear on the tail drive pully was gone. After removing the pulley assembly there was nothing left of the belt gear other than the flat ends.

Anyone else ever have a problem like this? This was something I never would have expected to wear totally away. Reading about all the problems some have with spinning this is something I would not normally check. One more thing to add to the trouble shooting list guys.

 

[callsign4223]

I just had the exact same problem on my blade 400. They use the same tail drive pulley. The pulley on mine was still there but completely worn smooth. There are aluminum replacements available online for $8.99, only $3 more than the stock plastic version. I went with a plastic replacement just because my LHS had it in stock.

By the way, when mine lost tail hold I crashed and blew $50 in parts for not checking a $4 part.

You can check it really easy though. Hold the main blades solid and try to spin the tail blades. If you can spin them then you need to check that gear. It is possible to spin them if that gear is good, but it takes a LOT of force compared to when that gear is bad. If you have done it both ways you will be able to tell right away if that gear is going bad.

 

[RMB677]

Matt, The tail drive pulley that failed is the one in the main part of the body, BLH1655. I didn't notice any upgrade version on Horizon's site. I know upgrades are available for the assembly on the tail. Do you have info for the body pulley?

 

[BOKI]

RMB677; To bad you had a crash it doesn't take much to do some damage! Wrecked my Trex 450 & it was my fault but had some damage & had to do a Rebuild! Better check My belt & tail ! Never noticed anything though but I'm going to check again! The Best & good luck on your rebuild! Dave

 

[RMB677]

Matt, I did find the aluminum pulley on the Horizon parts list under "hop ups". Since the repair parts were ordered this morning guess I'll order it as a spare next time I need to place an order with them.

 

[callsign4223]

I have read on a few places that these pulleys do this. I don't know why HH doesn't just send it with the aluminum part since it's not that much more expensive.

 

[murankar]

Wow, I just posted on your blog. Maybe I should have gotten caught up on the forum first. Anyhow good luck getting back in the air.

 

[RMB677]

All my repair parts have arrived. Now I need to find the time to do the installations. Working all day today, need to go to a funeral home Sunday (bosses brother-in-law passed away), and covering the store all day Monday and maybe Tuesday. At least the extra hours will more than cover the parts cost.

 

[RMB677]

My Blade 450 is back together I've tracked the blades and its all set to fly. The wind today is gusting pretty good so other that a brief liftoff in the garage to make sure it works I'll have to wait for a calm day. .

It'll probably be Wed. before I have time to start on the HBK. There's a bit more involved in it's repair. I'll be installing an aluminum head assembly which means I'll have to level swash plate, set pitch of the blades, etc.

 

[RMB677]

Both helis are air worthy, test flew the Blade, all ok. The HBK is ready for testing as soon as weather and time allow. See my blog "Almsot Grounded" for more comments.

 

[Tony]

I just wanted to let you know, you can create multiple blog posts on each update rather than just commenting to your latest one.