posted on Jul, 15 2020 @ 05:12 PM
a reply to: Bigburgh
You have three airspeeds. Indicated, True, and Ground. Indicated airspeed is the speed shown in the cockpit, as measured by the pitot tubes and
static system. True is the actual airspeed being flown. Ground is how fast you're going over the ground.
Indicated airspeed can be affected by pressure changes. This is one of the instruments they're setting when you hear them give a pressure reading.
It's also what is used for setting maximum speeds.
True airspeed is how fast the aircraft is flying relative to the air mass around it.
Ground speed is where it gets fun. This has absolutely nothing to do with how fast the aircraft is actually flying. It is affected by either tail or
head winds. In the case of a tail wind, the indicated airspeed will show 500 knots, but the ground speed will show 700+, depending on wind speed. The
aircraft is flying 500 knots, but the transponder is reporting in ground speed, so shows 700, or whatever the ground speed is.
In the event of a head wind, the aircraft will show a slower speed on anything tracking it. In fact, depending on the aircraft, you could have a
negative ground speed. You're still flying above stall speed, but relative to the ground, you appear to be going backwards. This is normally seen in
So when you see 700+, there's absolutely no danger of the wings coming off, because the actual speed is much lower.