Flight Safety,. .. .I'm sorry, but you're wrong.. .. .There are not three distinct frames of reference. A frame of reference is something you purposely or inadvertently choose when you make a measurement. That reference frame is either inertial or non-inertial. There are an infinite number of choices of each. It has nothing to do with what reference frame you put the observer in. You could observe someone putting on a merry go round while doing aerobatics...makes no difference to the reference frame of the golf ball.. .. .A free body diagram is not a reference frame. It is a simplification of reality chosen to illustrates something. When you make some sort of measurement on your free body diagram, you are selecting a reference frame. That frame is inertial or non-inertial.. .. .Centrifugal and centripetal forces are the same magnitude and they point in opposite directions, but it is wrong to call them equal and opposite. Very very wrong. Tell that guy at Sikorsky to stop embarassing his company. The fact is, centrifugal forces can be observed in one reference frame where a centripetal force is produced in a different one. Because they can't both be observed equally and oppositely in one reference frame, they are not equal and opposing forces.. .. ."
You’ll note that in most cases the “drag” force does not exist if the “thrust” force does not exist." Not at all. If this were true then gliders wouldn't have any drag. Drag is a force that is dependant on velocity, not on thrust.. .. .Finally, you claim that "
the physics community is in a state of serious confusion". No, physicist understand fully the difference between real and apparent forces. It's others that get it wrong.. .. .If a physicist went to a biologist and said, "That's not an amoeba, it's a jelly bug." and then insisted that all amoebas should now be called jelly bugs, does that mean the biology community is in a state of confustion?. .. .Take expert advice from experts. Not people who use a little bit of the knowledge, not people who answer the phone at big companies, not self proclaimed experts who have too much time on their hands so make long posts on the internet ( <img border="0" title="" alt="[Big Grin]" src="biggrin.gif" /> am I the kettle or the pot). Take advice from those who study in that area.. .. .Last point. Why is an apparent force called a force at all? I guess the simplest answer is "if it talks like a duck and walks like a duck, call it a duck." When my copilot turns too sharply and pins me to my seat while I'm trying to drink some coffee, I don't think "hmmm...that felt a lot like a force but because I know some physics it totally wasn't". It feels just like a force, much of the physics we can study on that force work the same as real forces. Force is a good word for something that accelerates you, even when it's observed only because the seat you're sitting in gets accelerated.. . . . <small>[ 18 March 2002, 19:29: Message edited by: heedm ]</small>