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Suppose an unpowered parafoil (e.g. a ram air parachute or paraglider) is descending (gliding) in a standard atmosphere. Suppose a pitot tube is positioned to always point into the relative wind (e.g. hanging by a string with fletching) and is recording IAS.

1. I know that the TAS (true air speed) is expected to be higher at higher altitudes due to the reduced drag. How is the IAS (indicated air speed) expected to change with altitude?

2. Would the answer be different for a fixed wing glider? In other words, does the self-adjusting/ pendular pitch of the parafoil affect the IAS it stabilizes at?

Edit: Let's assume there is no control input from the pilot or any other changes taking place that are unrelated to altitude.

Suppose an unpowered parafoil (e.g. a ram air parachute or paraglider) is descending (gliding) in a standard atmosphere. Suppose a pitot tube is positioned to always point into the relative wind (e.g. hanging by a string with fletching) and is recording IAS.

1. I know that the TAS (true air speed) is expected to be higher at higher altitudes due to the reduced drag. How is the IAS (indicated air speed) expected to change with altitude?

2. Would the answer be different for a fixed wing glider that has all control surfaces locked in a neutral position? In other words, does the self-adjusting/ pendular pitch of the parafoil affect the IAS it stabilizes at?

Edit: Let's assume there is no control input from the pilot or any other changes taking place that are unrelated to altitude.

Suppose an unpowered parafoil (e.g. a ram air parachute or paraglider) is descending (gliding) in a standard atmosphere. Suppose a pitot tube is positioned to always point into the relative wind (e.g. hanging by a string with fletching) and is recording IAS.

1. I know that the TAS (true air speed) is expected to be higher at higher altitudes due to the reduced drag. How is the IAS (indicated air speed) expected to change with altitude?

2. Would the answer be different for a fixed wing glider? In other words, does the self-adjusting/ pendular pitch of the parafoil affect the IAS it stabilizes at?

Suppose an unpowered parafoil (e.g. a ram air parachute or paraglider) is descending (gliding) in a standard atmosphere. Suppose a pitot tube is positioned to always point into the relative wind (e.g. hanging by a string with fletching) and is recording IAS.

1. I know that the TAS (true air speed) is expected to be higher at higher altitudes due to the reduced drag. How is the IAS (indicated air speed) expected to change with altitude?

2. Would the answer be different for a fixed wing glider? In other words, does the self-adjusting/ pendular pitch of the parafoil affect the IAS it stabilizes at?

Edit: Let's assume there is no control input from the pilot or any other changes taking place that are unrelated to altitude.