Just a curiosity about CG movement. Anyone know how much the CG moves when converting a Series 7 between trigear and tailwheel configurations?
Just a curiosity about CG movement. Anyone know how much the CG moves when converting a Series 7 between trigear and tailwheel configurations?
- Gary
S7 SuperSport Tri-gear
w/Rotax 912, Oratex, Dynon
I'll bet the CG is in a sweeter spot with the tri-gear. As a tail dragger my SS7 CG is always very much toward the rear no matter how I load it. It stays within the limits, but always toward the rear limit.
Jim Ott
Portland, OR
Kitfox SS7 flying
Rotax 912ULS
John Evens
Arvada, CO
Kitfox SS7 N27JE
EAA Lifetime
Chap. 43 honorary Lifetime
You're absolutely right John, however I still really like my lithium battery. It doesn't do anything to help CG, but it saves 10 lbs, which is a lot of baggage and helps make up for my heavy tailwheel. It is also nice to not have to always hook up a trickle charger because it doesn't lose 1/10th of a volt in months of sitting.
Jim Ott
Portland, OR
Kitfox SS7 flying
Rotax 912ULS
Paul Z might be able to comment on this. He had his SS7 converted from a tri-gear to a tail wheel.
Where are you Paul Z?
Ralph
For five years I worked on the ramp at KSFO,s United Airlines ramp area. This was a few years after the Arab Oil Embargo. I found it curious that they would load every departing flight to nearly the aft CG limit. I learned that during the embargo anything and everything that would improve fuel economy was employed. Aft CG is very efficient. Improving airspeed and or economy depending on one's preference.
An aft CG, within operational limits at the same loaded weight, also allows a slower touchdown speed and slightly shorter rollout in many aircraft...with a forward CG bias a person may run out of elevator to keep the nose up before they run out of airspeed.
Dave S
Kitfox 7 Trigear (Flying since 2009)
912ULS Warp Drive
St Paul, MN
Yep, many aircraft display that characteristic. I know my Thorp is faster with baggage & a passenger than without.
John Evens
Arvada, CO
Kitfox SS7 N27JE
EAA Lifetime
Chap. 43 honorary Lifetime
A good illustrated read on the benefits of an aft CG (within limits):
http://www.boldmethod.com/learn-to-f...t-performance/
RobS
I'll have to got to the airport tomorrow to get the tail dragger weight & balance. Once I get both I'll post them.
Paul Zimmermann
Paul Zimmermann
LSRM-A
Garland, Texas