RocketmanAL Posted October 21, 2023 Share Posted October 21, 2023 The Mach number portion of the speedometer appears to be off. It is showing a higher Mach number than the aircraft is actually flying according to TAS. Steps to replicate: Add SU-25T and set it to start at M= .8, 20kft, TAS should be 496 kts. Jumping in the plane it shows the plane at M= .92. Indicated M=.8 occurs around 432 kts. Link to comment Share on other sites More sharing options...
Mike_Romeo Posted October 21, 2023 Share Posted October 21, 2023 1 hour ago, RocketmanAL said: The Mach number portion of the speedometer appears to be off. It is showing a higher Mach number than the aircraft is actually flying according to TAS. Steps to replicate: Add SU-25T and set it to start at M= .8, 20kft, TAS should be 496 kts. Jumping in the plane it shows the plane at M= .92. Indicated M=.8 occurs around 432 kts. Mach speed changes with air temperature, air pressure and humidity too. I hope you have taken these into account too. My skins Link to comment Share on other sites More sharing options...
razo+r Posted October 21, 2023 Share Posted October 21, 2023 19 minutes ago, Mike_Romeo said: Mach speed changes with air temperature, air pressure and humidity too. I hope you have taken these into account too. I tried at ISA atmo and saw the same. Link to comment Share on other sites More sharing options...
RocketmanAL Posted October 22, 2023 Author Share Posted October 22, 2023 4 hours ago, Mike_Romeo said: Mach speed changes with air temperature, air pressure and humidity too. I hope you have taken these into account too. I checked multiple different aircraft as part of testing I'm doing. Same altitude, same speed, same mission. The SU-25T was the only one to have a different TAS at M= .8. Link to comment Share on other sites More sharing options...
Solution Skuva Posted October 22, 2023 Solution Share Posted October 22, 2023 (edited) I think the confusion is that the inside numbers on the 25's indicator are not Mach. The indicator on the Su-25 (A and T) gives IAS and TAS While the indicator on Su-27/33 gives IAS and Mach Edited October 22, 2023 by Skuva 3 Link to comment Share on other sites More sharing options...
Ironhand Posted October 23, 2023 Share Posted October 23, 2023 (edited) On 10/21/2023 at 9:33 PM, RocketmanAL said: I checked multiple different aircraft as part of testing I'm doing. Same altitude, same speed, same mission. The SU-25T was the only one to have a different TAS at M= .8. Just curious. Where are you getting the Mach number from? Neither the Su-25 nor the Su-25T has a Mach meter. If I start at 20,000 ft in either the Su-25T or the Su-27 with the Mach set to 0.8 in the ME, I get identical TAS numbers. Mach Test.miz Edited October 23, 2023 by Ironhand Added: "in the ME" for clarity 2 YouTube Channel: https://www.youtube.com/channel/UCU1...CR6IZ7crfdZxDg _____ Win 10 Pro x64, ASUS Z97 Pro MoBo, Intel i7-4790K, EVGA GTX 970 4GB, HyperX Savage 32GB, Samsung 850 EVO 250 GB SSD, 2x Seagate Hybrid Drive 2TB Raid 0. Link to comment Share on other sites More sharing options...
RocketmanAL Posted October 23, 2023 Author Share Posted October 23, 2023 14 hours ago, Skuva said: I think the confusion is that the inside numbers on the 25's indicator are not Mach. Ah, that would be the answer! Thanks for the clarification. Link to comment Share on other sites More sharing options...
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