G-force
 

Does anybody used a log system like
http://www.rc-cam.co.uk/Products_log_Land.htm
to measure positive and negative G’s acceleration ? I’d like to know data from real flights to make more perfect models.
(sorry for poor English)

RE: G-force
 

Vladimir

I find this device to be very useful.

I use it quite a bit for evaluating geometry of pattern flights, prop performance comparisons, and G-force loads on the airframe. For most evaluations I record 10 samples / second of 6 or 7 parameters which allows about 10 minutes of logging time. For detailed studies, say for snap roll loads, I may set the sample rate to 40 / sec.

Calibration checks should be devised if you're interested in absolute data, for comparison purposes the unit appears stable. As the altitude and airspeed sensors are pressure based, care must be exercised to prevent pressure variants where the unit is mounted. (Discussed in the instructions).

The best way to evaluate the data is by transferring the file to a spreadsheet (Excel) which will permit expanded graphic display of the data.

Your English is a whole lot better than my Russian!

RE: G-force
 

EHFAI,

What kind of G-forces do you see in your model and what type of A/C is it ???

Thanks

RE: G-force
 

3D JOY

I've only gathered G-force data during pattern maneuvers - no 3D, sorry. What I've gathered has been in a PL Partner and a Quique 72" YAK.

The Partner is smoother and slows better, typically 200' radius loops @ 70 mph or so will be 3 to 4 G's in the pitch axis. Max I've recorded is similar size 180 degree radius at the bottom of a reverse humpty - 7 G's @ 110 mph. Vertical or horizontal snaps are typically 5 to 6 G at the pitch break @ around 60mph.

I've looked at the Reverse Avalanche snap (inside loop from the top / + snap @ bottom). Again, 200' radius loop (about 5 G's) @ 90mph will register 12 G's at the pitch break. Slow to 80 mph and the G's drop to about 10. Essentially similar snap forces as seen with the Partner added to the loop G forces.

Snap G's peak rapidly during the pitch break, then drop off quickly during the stalled rotation. A buried snap or an unloaded snap looks similar.

All G-force data measured at the aircraft CG in the pitch axis.

RE: G-force
 

I'd like to see an agressive blender G's

RE: G-force
 

Thank you for information, that's just what i looked for.