Originally Posted by
hans brinker
I'm sorry, WHAT?? Airplanes do not fly relative to the ground, they fly relative to the air. If you fly an airplane at 60kts, against a 60kts headwind, you will be stationary over the ground, but you will not stall. If you make a 180 degree turn your groundspeed will now be 120 kts, but you will not exceed any aircraft speed limit. This applies in the patterns as well. If you are on the base leg and you have a headwind for landing, your turn to final will be a bit less than 90 degrees, due to the crab angle on base. Conversely, if you are landing with a tailwind your turn to final will be bigger that 90 degrees. If your approach speed is 90 kts, and you turn final in either cease, your indicated speed will (should) stay at 90 kts. Your ground speed will go up for a tailwind and down for a headwind, but your airplane wont realize that, because it's only reference is the air around it. I cannot believe there are pilots that think aerodynamics are affected by ground speed. Yes, landing distances are. Yes turn radiuses across the ground are. YOU WILL NOT LOSE AIRSPEED TURNING INTO A "TAILWIND".
Maybe read again, what I wrote.....
You think in speed. That's the wrong approach. You need to think in Kinetic Energy, and that is ground reference based. When you turn final with Kinetic Energy Ek, it represents a ground speed corresponding to that Ek. And you have the same Ek on your base leg, with the same ground speed. Kinetic Energy doesn't know about airspeed. Only wings know about airspeed.
IF you need a higher ground speed to keep flying (because of a tailwind), you will need to add Kinetic Energy. If you don't do that, by pointing the nose down (trading in potential energy) and/or use engine power (trading in chemical energy), you are loosing airspeed. The extra Kinetic Energy does come from somewhere. Really.