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View Full Version : Raptor 90 goes down


HeliRaptor
05-06-2007, 05:12 PM
I was out yesterday (Saturday April 28, 2007) with my buddy Jeff and several other club members at the field. The day started off great. We got Jeff's machine running finally (shimmed to 16 thousandths and used an Enya #3) and she now runs great.

I put my 1st 2 flights of the day on the 90 with nothing more than figure 8's, rolls, loops and a few back flips.

Later I went up for a 3rd flight and figured I would do a bit more, so I do a few figure 8's to be sure engine temp is up and I am comfortable. All is going well, I flip the machine inverted for just a few seconds not long at all, I got a little nervous and flipped it back right side up, during the flip I heard a weird noise, not sure whether or not it was my machine as everything else felt fine, I pulled it into a left turn and zipped down the field, I notice the engine seemed to have a higher pitch sound and I was getting less power to the head, head speed slowing down, I banked right and started to head back to land, and that's when the motor just whined but not headspeed, I immediately went into auto mode in my mind (The heli was only like 15 - 20 feet off the ground) but I was too low to regain head speed, I got it level and flared it as best I could but at about 4-5 feet I lost total head speed and she went in.

When I walked over to the Heli I noticed it was still running great, it went into a nice low idle like I set the failsafe to do if it loses communication with the TX, it did lose communication because when it hit I immediately turned off the TX to test the failsafe hoping that it will do what I set it to do to keep it from doing a dance.

Anyhow, the damage is not fully *****, but I got lucky and the main blades were intact but the tail is pretty beat up, tail blades junk, boom, torque tube, plastic frames front and back, landing gear and I'm sure there is more.

I realized at the field where the failure / error might have been. The White main gear was stripped of its teeth. I haven't checked it out as to what caused it but my only guess is that when I ***** it after replacing the pinion bearing that I must have improperly set the gear mesh. I find it odd as it flew with no issues before the mishap and there was no signs of gears being tight or being chewed up.

In any event the 90 is down. I went out and had a few to many drinks after that and got in around 2 AM and didn't want to even think about it.

More to come once I take a closer look at the damage, sorry no pics I didn't have the camera with me.

HeliRaptor
05-06-2007, 05:16 PM
Well, I took apart the entire helicopter to figure out what happened. I am sad to say that this crash was due to me over looking one piece during the re-***** of the helicopter after I replaced the Pinion Bearing. I am really surprised that I didn't catch this when I lifted the machine by the head. If I never went inverted I would have never had the crash. Lesson learned "DO NOT WORK ON HELI LATE AT NIGHT WHEN TIRED" the hard way.

So here's what happened. When I re-***** part number PV0154 (See pics) the lower bearing block for the main mast I accidentally installed it upside down (reversed). By doing this I caused about 1/8" of play in the main mast which I never noticed. So while flying right side up there will not be any notice of this being an issue. When I went inverted and the helis weight and the way the thrusting of the head works I moved the main mast the 1/8" towards the edge of the clutch bell which caused the machine to most likely skip a tooth therefore breaking a one tooth and it eating the rest.

Pretty sad that I didn't catch the bearing block being upside down, had this not happened I would still have my machine in one piece.

Anyway here is a breakdown of the damage. All prices are from HeliProz. The actual damage is less than previously thought.

YB105 Tail Blades - Curtis Youngblood Radix 105mm $ 32.99
PV0164 Tail Fins $ 9.99
PV0421 Torque Tube $ 21.99
PV0422 Tail Boom $ 19.99
PV0161 Landing Skids $ 18.99
PV0298 91 Tooth Main Gear $ 10.29
PV0412 Fan Shroud $ 22.99
PV0157 Rear Plastic Frame $ 7.49
PV0169 Link Rods (For Double Link) $ 6.89
PV0041 Plastic Links for link rods $ 7.99
PV0416 Tail Control Rod $ 8.99
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Total crash cost $168.59 plus shipping

HeliRaptor
05-06-2007, 05:21 PM
So I thought I would share the extent that I took this machine apart to make sure there are no other problems that may be hidden before she sees the sky's again.

cxdogfly1000
05-06-2007, 05:28 PM
sorry crash helirappter hop fly soon. do think a rapter 620 OK some Farly now heli nice reter 90
i got the g3 sim

heli-cuzz
05-06-2007, 08:33 PM
Sorry to hear, D. A buck 68 isn't to bad. :) Your mains were ok, that saved you a few $$.