Mark Landoll Harmonic Dampener question

OneTwoSierra · #1 06-30-2006, 01:13 PM

A buddy loaned me a Mark Landoll Harmonic Dampener to try. I have a catto 3-blade prop, so I'm not really expecting a ton of benefit from vibration, but I it'll get me closer to forward CG. Maybe I'll get better idle or more static RPMs.

Is there anything I need to know before I just bolt this on and go flying? I haven't heard much about them lately, and I was just wondering if they've fallen out of favor for some reason.

I have scales, so I'll know exactly what the CG impact.

Thanks in advanced,

godspeed · #2 06-30-2006, 02:17 PM

Hope you get some replies on this one, I am wondering the same thing.. is the CG that bad ?

Danny..

pierre smith · #3 06-30-2006, 02:33 PM

Brian,
We have a 6A with a three-bladed Catto and the CG is fine with two people, full gas and no baggage. You won't get any more static RPM because the pitch determines that but maybe a smoother idle. Ours idles smooth already and I don't want to add any more weight to the airplane (It came in at 1046 lbs unpainted). A slightly rearward cg will increase your speed since a little 'down' elevator supporting some of the airplane's total weight is taken OFF the wing for a lower angle of attack. I intentionally fly with an aft CG when I can for that reason and we get 202 MPH true with two aboard and full fuel.(205 solo). Wife and I weigh 190 and 135.

It's only when you have a very far aft CG with baggage that the CG will move even further aft as the fuel burns and the elevator will become more sensitive and lighter but that's not a biggie either, if you're still in the balance envelope

It seems to me that you think you have a problem when you really don't. Keep the airplane light and don't spend bucks on things like harmonic balancers if you don't need them. After all, how many other Lyc powered airplanes carry them around?

One caveat though. Don't go doing spins with a very far aft CG or any other maneuver that might cause a spin.
Regards,

pierre smith · #4 06-30-2006, 02:35 PM

'Scuze me,

I weigh 190, wife is 135.......

OneTwoSierra · #5 06-30-2006, 02:45 PM

Quote:

Originally Posted by godspeed

Hope you get some replies on this one, I am wondering the same thing.. is the CG that bad ?

Danny..

No, my CG isn't bad. I just want to really load her up for OSH. With my 220 lb. wife and my 125 ib. self (just kidding, Pierre cracked me up.), we can carry a ton, but just not a ton in the baggage compartment. If I had more weight up front, I could get away with over 100 lbs in the baggage compartment that I might need going to OSH.

So just so no one misunderstands, I'm really thinking about trying this thing just to see what it's like -- I really don't have any particular issue I need to solve.

And, to answer an earlier post, some have claimed 75 to 100 more static RPMs with these things due to the smoothing of the engine and absorbtion of the pulses. I have no way of knowing if that's true or not yet.

godspeed · #6 06-30-2006, 03:05 PM

I would love to know how things work out when or
if you test it, I don't plan on going over the 75lbs in the baggage, my plan is board shorts, superman teeshirt & flipflops headed to the keys

maybe a hangin shirt for going out to eat at night

2 or 3 lbs
but thats just me dreaming, anyway hope ya'lls wife
doesn't see that post.. how old did you say they were

just kidding.. I am divorced so I can tease like that.. after 20 years of marriage..

Danny..

#7 06-30-2006, 05:45 PM

I have a 7A with a Performance wood prop and a Landoll Dampener. My plane came in at 1067 w/o paint and interior. I flew 20 hrs w/o the damper and the prop / engine combo was smooth running. The only changes I saw when I put the damper on was the ability to idle at 650 RPM vs 700, smoother idle, and the prop does not "slam" to a stop on shut down. I haven't noticed much difference in cruise...

I weigh 265 and with a friend who is 220 the extra weight in front does help the CG loading when baggage is carried. I set my gross at 1900 since I have fat friends...

Are the changes worth the money? Probably not....

Wally · #8 03-13-2016, 06:58 PM

Would like to communicate with anyone who is or has used a Landoll Harmonic Dampener. Post, PM or phone.

Thanks.

moosepileit · #9 03-13-2016, 07:10 PM

Are current prop bolts long enough to use with the Landoll?

Kyle Boatright · #10 03-13-2016, 07:31 PM

Quote:

Originally Posted by moosepileit

Are current prop bolts long enough to use with the Landoll?

The ones I've seen attach to the flywheel ring and do not impact the prop or its bolts.