Author Topic: 109G2 - not a bad little airplane (Read 2179 times)

GScholz · « **Reply #45 on:** October 29, 2003, 07:20:31 PM »

No, I'm talking about when the plane is compressed, but not completely unresponsive. I'm sure you're aware that planes don't just hit compression like it was a wall, it's a gradual process as speed increases beyond a certain point. Try this: Grab a 109 or a Zeke or any other plane that's prone to compression. Grab some alt and start accelerating in a shallow dive. As compression starts to set in pull back on the controls to find out how many G's you can pull. Then trim the nose up and watch as the plane climbs faster and faster with the stick pulled back. When the 109G10 hits about 500 mph it starts to compress, and without trimming you cannot pull more than 4 to 5 G's, trim up and you'll do blackout turns with ease. It works I guarantee it, because a use it every time I fly in AH.

Blue Mako · « **Reply #46 on:** October 29, 2003, 07:42:49 PM »

GS,

Compression results from the hinge moments of the control surfaces (ie. the control forces) becoming too great to overcome by stick force alone. Trimming a control surface changes the hinge moment, thus changing the stick forces. As I stated above, the advantages of manually trimming are only found in the compression region where this is an issue. No doubt HT have modelled a cut-off point where the stick forces would be too great without trimming to move the controls, giving the compression effects.

The common misconception that I was originally refuting was that manually trimming for a normal turning fight outside of the compression region gives an advantage over combat trim, which it does not.

Sorry I missed in your original comment that you were talking about the compression region.

GScholz · « **Reply #47 on:** October 29, 2003, 08:22:16 PM »

Compression is actually the formation of local supersonic airflow over the controls which had negative and often not understood effects (P-38 for instance had a nasty tendency to nose over in a death dive). In AH compression is AFAIK just modelled as increased stick force. Although I understand that the FM changes are made for every plane due to programming considerations a few planes were able to trim beyond the otherwise maximum deflection of the controls. The 109 for instance moved the entire horizontal stabiliser as trim, naturally increasing the effective maximum deflection of the elevators mounted on the stabiliser. This is a minor detail however as I always seem to be able to pull that damn thing into a stall in slow fights.

Blue Mako · « **Reply #48 on:** October 30, 2003, 04:49:03 PM »

Quote

Originally posted by GScholz
Compression is actually the formation of local supersonic airflow over the...

Yup. This leads to the control forces being too large for the pilot to overcome. I was just trying to keep it simple, I've done several years of study to get my degree on this stuff...