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407 Mainrotor Tracking

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fairly new to 407. followed the book and got it in nicely. but seemed to take a lot more runs than i liked. book says pitch links on the ground. tabs in flight. seems funny that you do the slow speed and then then move to highspeed, all tabs. you get it smooth at the top end and the bottom end messes up a bit.

this normal? did a little chasing different blades, sure like it to go a little quicker.

thanks

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The 407 can turn into project to get balanced. I do the ground (35%Q) runs until the track is dead on. The do the same for hover. Seems like overkill but it works. Make sure the PC rod ends are centered top and bottom on the threads. More than once I've run into runing out of threads and had to start over.

 

You'll hear "roll against tab" on this head you have to do it sometimes (tab up/Pc Down) to get the right effect of the weight.

 

If it starts turning into a marathon session and you cant get either low speed or high speed to both come below limits, start looking at the corner mounts and restraints. One nice thing is that once it's balanced it really never goes out unless one of the elastomeres starts going south.

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The 407 can turn into project to get balanced. I do the ground (35%Q) runs until the track is dead on. The do the same for hover. Seems like overkill but it works. Make sure the PC rod ends are centered top and bottom on the threads. More than once I've run into runing out of threads and had to start over.

 

You'll hear "roll against tab" on this head you have to do it sometimes (tab up/Pc Down) to get the right effect of the weight.

 

If it starts turning into a marathon session and you cant get either low speed or high speed to both come below limits, start looking at the corner mounts and restraints. One nice thing is that once it's balanced it really never goes out unless one of the elastomeres starts going south.

 

yes. did seem a bit of project. i messed with the were it started getting rough and played too long with that. then i just went as you said. start at the beginning from the ground. still took a bit. but every move got closer. funny the maintenance manual says use pitch links on the ground only and tab in the hover. where the vib meter that we use and is also for the 407, states pitch links in the hover, where i have used many times on other a/c. worked well.

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I once spent five days tracking a 500 after a single blade change.

Not because I was an idiot, more because we had 3hrs of daylight and we're in the middle of a drill move at the time and at -40C....

I feel your pain on not being expediant with the proceedure...but hey, be glad you weren't me at that time.

 

Always remember, you'll get better at it with time.

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Hi while I haven't any experience with the 407. I have lot's of experiance with the 500 and multi bladed systems. My best advice is to fill the thing full of fuel throw a ladder in the back of the machine and get away from the maintenance base and follow your instincts. Maybe talk to a few trusted people and yes even a experienced pilot on type can help you out a bit. But most importantly follow your head and don't allways believe that the blades have to be in track to give you the smoothest ride. You will remember much better when you actually do it not the guys at the hanger giving you the advice.

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I think we all balance multi-bladed helicopters. Haven't had the honor of working on a single bladed head...Sorry had to take that shot.

 

Agreed on getting involved with dymanic balance by committe. If I have the chance, I'll go off in the corner by myself.

 

Granted the best ride doesn't always come from the blades being in perfect track. The 407 really goes faster if you take the time in the ground and hover runs to get the track within a couple milimeters total spread. They might not end up there at VNE but to not doing it usually causes you to start chasing yout tail.

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Can only say that I have had the pleasure working with engineers who do not take advice and spend three hours figuring out how the strobex works rather than ask. Was with two ame's who turned the pitch rod backwards three times getting the 204C a foot out of track at idle. Have also had the pleasure of doing 30 friggin runs accomplishing nothing but turning fuel to noise while the AME figures it out his way. The most important thing with any tracking and balancing is to have an open mind to other ideas and methods all the while doing it by the book. If things are not going well ask why. Usually there is a old timer or young smart fella who has an answer which will work. Also understand that track effects balance and vice versa to an extent so sometimes a double check of what you think is already been done is necessary.

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Can only say that I have had the pleasure working with engineers who do not take advice and spend three hours figuring out how the strobex works rather than ask. Was with two ame's who turned the pitch rod backwards three times getting the 204C a foot out of track at idle. Have also had the pleasure of doing 30 friggin runs accomplishing nothing but turning fuel to noise while the AME figures it out his way. The most important thing with any tracking and balancing is to have an open mind to other ideas and methods all the while doing it by the book. If things are not going well ask why. Usually there is a old timer or young smart fella who has an answer which will work. Also understand that track effects balance and vice versa to an extent so sometimes a double check of what you think is already been done is necessary.

 

Jeez, I hear you there Scully. I was one engineer that was never happy or adept at using a strobe. Intimidated the bejeez out of me. I would do anything to avoid it including crying as required! I think the main problem was I never actually received a course or good instruction. I also know for sure that there are plenty of Engineers out there that are/were in the same position as me.

The funny thing is though, that in the bad old days all I needed was a tracking flag, a grease pencil taped to a stick and a roll of masking tape and I could make a S-55 or any Bell 47 fly as smooth as glass. Go figure!!

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Can only say that I have had the pleasure working with engineers who do not take advice and spend three hours figuring out how the strobex works rather than ask. Was with two ame's who turned the pitch rod backwards three times getting the 204C a foot out of track at idle. Have also had the pleasure of doing 30 friggin runs accomplishing nothing but turning fuel to noise while the AME figures it out his way. The most important thing with any tracking and balancing is to have an open mind to other ideas and methods all the while doing it by the book. If things are not going well ask why. Usually there is a old timer or young smart fella who has an answer which will work. Also understand that track effects balance and vice versa to an extent so sometimes a double check of what you think is already been done is necessary.

 

 

While I agree with your statement about not being familiar with the equipment can cause you a bunch of grief. It also is up to the individual to take it upon themselves when they are realize that they are in over their head and ask for help be it from a experienced pilot or another AME . I also agree It can be frustrating to watch somebody learn on your time. I can also attest to hours spent chasing a snag due to a pilot not being familiar with an aircraft and or equipment. I still stand by my statement it is best to go out there and figure stuff on there own, you learn much better. It has worked well for me and each time I spent chasing my tail it helped me for future decisions in similar situations.

 

 

Red Rag well I guess I can say I left myself open to that one.

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Was with two ame's who turned the pitch rod backwards three times getting the 204C a foot out of track at idle.

 

I remember that! I think it was over a foot out of track at 30% actually... Ha ha ha... And when the DOM asked the lead engineer what the problem was the guy said "Tired! Friggin' tired!"... Gong show...

 

HV

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