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Do I need more weight in the nose?

walkman

walkman

Well Known Member
When I'm at cruise, the forward edge of the elevator counter weights sticks up above the surface of the horizontal stab by about 1/3".

I'm loosing at least a nano knot!

Every airplane I've ever owned had those lined up close to perfectly in cruise.

Can I fix this? Should I?
 
Martin, that's typical,...my -10 is like that and so was my -6A. That's a good thing because the tail is holding up some of the load, relieving the wing of that weight....and you go faster.

Best,
 
Put any carry-on stuff (tool kit, survival kit, canopy cover, tie downs, quart of oil, etc.) in the forward baggage compartment until the elevator is in the trailing position. Sorry, can't help you on the 6.

Jim
 
@Low pass

Yes, typical xcountry config is solo, with 10lbs of tools and oil, plus a medium duffel bag in the front. In this trip I had 5 gals of smoke oil in the rear baggage but that made little difference.
 
walkman said:
@Low pass

Yes, typical xcountry config is solo, with 10lbs of tools and oil, plus a medium duffel bag in the front. In this trip I had 5 gals of smoke oil in the rear baggage but that made little difference.
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So, you said the counterweight is 1/3" high when flying solo in the -8. That sounds reverse of how it should (generally) be. Start by double checking your CG. Then look at the HS incidence. Have you flown it at aft CG? What'd the counterweight position look like there?

If the CG checks out, and the controlability at aft CG is good, then the cure is probably worse than the condition.
 
Van would tell you that a slight amount of down elevator at cruise is good- you're shedding some of the downforce carried by the tail.
 
The 8 is already a nose heavy aircraft and can run out of elevator on landing. Can't imagine wanting to add weight up front. Maybe your w&b is different but I would certainly start there.
 
Kyle Boatright said:
Van would tell you that a slight amount of down elevator at cruise is good- you're shedding some of the downforce carried by the tail.
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Not with the rear seat empty. This is an -8, as I understand the OP. To the best of my recollection, my elevator is neutral with a tool bag in the aft baggage, 2-3 qts of oil up front and me alone. Load up the back and the elevator drops (counterweight rises).
 
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The horizontal stab and elevator "lift" downward in normal configuration. This is wasted lift for carrying the aircraft and excess induced drag. If you can get the horizontal tail group closer to neutral lift, there is less induced drag from a surface not carrying the weight of the aircraft but balancing the cg forward of the center of lift. Less induced drag equals more speed. Some gliders have weight they can shift fore and aft in flight for this purpose
 
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