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viktorradnai / flightgear-ask21

ASK21 glider model for Flightgear
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Adjust glide-angle #47

Closed ghost closed 7 years ago

ghost commented 7 years ago

see https://forum.flightgear.org/viewtopic.php?f=4&t=31363#p302600

The sink rate in normal flight is abnormally low. I have not tried to calculate it, but it should be somewhere just below 1 m/s.

This is probably caused because the yasim glide-angle is not as expected, so massive testing with different values will be required.

viktorradnai commented 7 years ago

Minimum sink for an ASK21 is about 0.5m/s. If we're lucky the manual might have a polar curve.

On 4 Jan 2017 9:31 a.m., "D-ECHO" notifications@github.com wrote:

see https://forum.flightgear.org/viewtopic.php?f=4&t=31363#p302600

The sink rate in normal flight is abnormally low. I have not tried to calculate it, but it should be somewhere just below 1 m/s. This is probably caused because the yasim glide-angle is not as expected, so massive testing with different values will be required.

— You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub https://github.com/viktorradnai/flightgear-ask21/issues/47, or mute the thread https://github.com/notifications/unsubscribe-auth/AEhMgl7RTgGuLQpo06Fc0qObQ5AxIJy-ks5rO1j-gaJpZM4LaZEB .

viktorradnai commented 7 years ago

ASK21 polar curve is here: http://www.fsglider.de/p_pol_e.htm

The are a couple of different versions, I need to compare them to make sure that the data is the same.

On 4 Jan 2017 09:53, "Viktor Radnai" viktor.radnai@gmail.com wrote:

Minimum sink for an ASK21 is about 0.5m/s. If we're lucky the manual might have a polar curve.

On 4 Jan 2017 9:31 a.m., "D-ECHO" notifications@github.com wrote:

see https://forum.flightgear.org/viewtopic.php?f=4&t=31363#p302600

The sink rate in normal flight is abnormally low. I have not tried to calculate it, but it should be somewhere just below 1 m/s. This is probably caused because the yasim glide-angle is not as expected, so massive testing with different values will be required.

— You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub https://github.com/viktorradnai/flightgear-ask21/issues/47, or mute the thread https://github.com/notifications/unsubscribe-auth/AEhMgl7RTgGuLQpo06Fc0qObQ5AxIJy-ks5rO1j-gaJpZM4LaZEB .

ghost commented 7 years ago

So from the polar curve we should get a sink rate of 0.75 at 90 km/h, I will test this [EDIT]I got 0.17m/s, so yes, it's far too good

ghost commented 7 years ago

Please try with 4.5 for cruise and 5 for approach, that worked quite well for me

viktorradnai commented 7 years ago

See #49

ghost commented 7 years ago

Fine now :D