Quote:
Originally Posted by V1.47fan
A vertical speed indicator determines the rate of climb, it doesnt give you IAS or ground speed and yes some VSI's use accelerometers.
Accelerometers measures g forces, not ground speed or airspeed.
That's why modern airliners (to the latest 787, A350) still rely on the old pitot-static system for airspeed.
...f you've figured out a different way to determine airspeed using accelerometers you should share it with the world.
|
You're right. However, you are also the only one talking about airspeed and accelerometers. The discussion started talking about ground speed.
Ground speed is simply a velocity, as is vertical speed. Accelerometers can be used to determine either (knowing how much the aircraft has accelerated means that the speed can be derived).
The
primary source for most modern aircraft's vertical speed is now accelerometers (pitot system as a backup - the diagram is old skool tech). The
primary source of groundspeed is GPS, but there is often an accelerometer-based back-up in case GPS signal is lost. This is much more accurate that the old gyro-based inertial nav systems.
The
only source for airspeed is the pitot-static system.
So, in sum. Groundspeed is available using accelerometers as the data source. Airspeed is not - but then that's not what we started talking about.
Enough nerding - I'm off for a glass of wine!
