PW-5 longitudinal pitch oscillation

So I increased the ballast weight in the PW-5 from parachute + 20 pounds to parachute + 40 pounds. The pitch stability increased noticeably, i.e. uncommanded nose-down excursions diminished.

Thanks all; I've enjoyed reading about model gliders and changes upon entering thermals.

On Wednesday, September 13, 2017 at 6:10:58 PM UTC-7, wrote:
So I increased the ballast weight in the PW-5 from parachute + 20 pounds to parachute + 40 pounds. The pitch stability increased noticeably, i.e. uncommanded nose-down excursions diminished.

Thanks all; I've enjoyed reading about model gliders and changes upon entering thermals.

In my only flight in the PeeWee had hoped to do spins.
Couldn't get it to stall, even accelerated, so gave up on spins.
That was with no nose weight. Perhaps it could use tail weight?
Like the OP, with way forward C/G, didn't notice any tendency to oscillate in pitch. It still climbed well, don't ask about cruise.
Did notice turbulence perhaps from the large access hole in the horizontal stab. Now there is no World Class and associated rules, that design problem could be fixed with mylar.
Jim

Originally Posted by JS[_5_]

On Wednesday, September 13, 2017 at 6:10:58 PM UTC-7, wrote:
So I increased the ballast weight in the PW-5 from parachute + 20 pounds to parachute + 40 pounds. The pitch stability increased noticeably, i.e. uncommanded nose-down excursions diminished.

Thanks all; I've enjoyed reading about model gliders and changes upon entering thermals.

In my only flight in the PeeWee had hoped to do spins.
Couldn't get it to stall, even accelerated, so gave up on spins.
That was with no nose weight. Perhaps it could use tail weight?
Like the OP, with way forward C/G, didn't notice any tendency to oscillate in pitch. It still climbed well, don't ask about cruise.
Did notice turbulence perhaps from the large access hole in the horizontal stab. Now there is no World Class and associated rules, that design problem could be fixed with mylar.
Jim

Well, the POH is pretty clear at higher pilot weights the aircraft will NOT stall with full aft stick...