Cessna 172 Skyhawk gauge vs HUD speed discrepancy

SU14 Beta

I believe that the plane’s gauge is correct and the HUD is off. Both should be IAS I am pretty sure.

It’s strange. If I slow down to around 100 kts (actual aircraft airspeed indicator) the outside view speed is significantly off. But if I cruise around at 2600 RPM, the two speeds are much closer to each other (and frequently exactly match) (IAS). So I think whatever calculation they used, was aimed more toward aligning them at cruise speeds, although they should always match each other. You would think it would just read the inside gauge and mirror it on the outside view.

The Panel Airspeed gauge has a Calibration knob, to adjust for outside air temperature, and provide a corrected air speed.

The HUD display displays what ?

Maybe the HUD display has programmatically done the air temperature compensation , and is displaying the corrected airspeed. (there is no temperature calibration KNOB on the HUD !! )

With no air temperature given in the original pictures, it difficult to tell - shame the CLOCK was displaying VOLTS and not TEMPERATURE !!

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If it’s an issue that appeared with the SU14 beta it should be reported in the beta bug section. Here’s the link to the SU14 beta section of the forum: Sim Update 14 Beta - Microsoft Flight Simulator Forums
Please use the bug report template if you make a new report there, as it helps the team check the reports quickly.

I don’t have access to the skyhawk on my standard beta account, so I can’t confirm this, but on SU13 live the hud IAS is perfectly accurate to the c172 skyhawk cockpit IAS gauge on my system.
I checked the C152 in SU14 beta and that also matches perfectly.

Replicated on SU13: No, tested.
Replicated on SU14: No, but unable to test c172 skyhawk.

You sure that is so with the Default C172SP (Steam gauge)
If you are looking at the wb-sim Enhansed MOD’s C172, (which I believe you have :+1:) it has that Panel indicated airspeed corrected to be calculated correctly !!

Empty community folder due to testing other stuff. Stock default c172 skyhawk on SU13.

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Good man !!

and as an added “perk” – your Assistance settings probably are not being reset !!

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I took a look earlier at the TAS adjustment to see if that affected the issue. Unfortunately, it doesn’t appear to be the issue. Once adjusted, the displayed TAS is quite a bit higher on the internal gauge than the speed shown on the external HUD at all speeds. However, As I mentioned, both gauges appear to display IAS pretty close to each other at cruise speeds, but well off from each other at slower than cruise speeds.
I was really hoping it was just caused by setting the correct Pressure altitude vs OAT and they were both reading TAS. No such luck…

This was all done with just one test flight, so there’s no absolute assurance it’s the correct interpretation of what’s happening.

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Sounds good – for anyone not that familar with Airspeed type, this is one of the best Youtbe videos on the subject for smaller GA planes.

Don’t let the Opening title put you off, the actual video is very good.

BTW. It is still not 100% certain that IAS is being calculated accurately in the sim, as displayed on the Airspeed Gauge,

Time to get you E6B out :wink:

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Hi N6722C,
My community folder has never had anything in it for my test version of MSFS, yet my assists are still resetting to easy after each restart.
Do you have any other ideas/hints/deities to sacrifice a plane to, to help work around this issue???

The only CRUDE work around I know of, till Asobo fixes the issue, is to have the Internet disconnected when you 1st start MSFS, utill after it times-out trying to get the Cloud data.

Quicker that having to re-select any custom Assistance settings.

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ie Selecting the Alt Static Port should noticeably alter the IAS - but it does not … :woozy_face:

This issue appeared with SU14 beta, it should be reported in the beta bug section.

This topic can be moved to the bug report section?

This issue appeared prior to the beta release. It is not unique to the beta. Thanks for your interest and thank you to all posters who have investigated this issue