These days, I fly the 172 with glass panels.

It seems that she cannot go faster than about 103 knots IAS at cruise. I generally fly at an altitude between 5500 to 8500 feet with the engine running at 2400 RPM and the mixture set at a little less than peak EGT.  Flaps are up, of course. 

I am not familiar with the 172. In P3D I had the A2A 182 and the Cherokee not the 172. 

Is it that the modelling is wrong (underpowered) or that I do not do something right ?

There is a problem with the "mixture" at higher altitudes, which is not correctly modeled. I turned Auto Mixture on (in the Assistance menu). Since then I don't have any power/speed problems. Before, I could not even take off at some higher altitude airports with shorter runways. I know it is less realistic but it is not a study level a/c either. I guess I can live with this until the a2a models arrive in MSFS.

Edited February 25, 20215 yr by Nemo

Hey Dominique,

I’ve got a few hundred hours on 172s and that doesn’t seem too far off, it would depend on the airframe as each would fly a little different, some would cruise a couple of knots faster than others!

Anthony 

100ish knots sounds about right for a 172. It's no rocket ship, and doesn't have as much power or the VP prop that the 182 has.

Also indicated airspeed will decrease as you climb and that's pretty high altitude for a 172.

Thanks to all who have already answered. Appreciated.

 

48 minutes ago, Tom Wright said:

100ish knots sounds about right for a 172. It's no rocket ship, and doesn't have as much power or the VP prop that the 182 has.

Also indicated airspeed will decrease as you climb and that's pretty high altitude for a 172.

The 172 as I read it in the in-sim presentation, is rated up to 14K feet and for a cruise speed of 124 knots.  I was then under the impression that I was flying at medium altitude and rather slower than expected. Are these ratings just Textron hype or an Asobo mistake ? 

cruise : 110-120 knots (and not mph...) at 2400 rpm 

play with mixture is  to not spare gazolin at high altitude : less oxygen, less gazolin ; dson't play over rpm unles you have it too lower...

45 minutes ago, Dominique_K said:

The 172 as I read it in the in-sim presentation, is rated up to 14K feet and for a cruise speed of 124 knots.  I was then under the impression that I was flying at medium altitude and rather slower than expected. Are these ratings just Textron hype or an Asobo mistake ? 

That's probably true air speed rather than indicated. 100kts IAS is plausibly around 120kts TAS at those sorts of altitudes, depending on the atmospherics. Indicated airspeed always comes down as you climb higher as the air gets thinner.

At 14k feet in a 172 you're probably going to be on oxygen!

33 minutes ago, Tom Wright said:

That's probably true air speed rather than indicated. 100kts IAS is plausibly around 120kts TAS at those sorts of altitudes, depending on the atmospherics. Indicated airspeed always comes down as you climb higher as the air gets thinner.

At 14k feet in a 172 you're probably going to be on oxygen!

I think you are right, the rated speed is indeed TAS. I am generally between 117 to 120 knots TAS.  

14K is a little high indeed.I seldom go over 10K and only when overflying a ridge.  

Thanks again, the 172 is not slow. I am. Age. 

Edited February 25, 20215 yr by Dominique_K

We used to fly a 172 SP with CSU prop and from memory it cruised around 115 IAS at the 5000 - 7000 sort of altitudes. So 105 indicated from a generic172 might be about right. (though this was 20 years ago so do not quote me on that it could be way out)

4 hours ago, Nemo said:

Before, I could not even take off at some higher altitude airports with shorter runways

Depending on atmospheric conditions, that’s completely realistic. Look up the term “density altitude”. 

2 hours ago, mtr75 said:

Depending on atmospheric conditions, that’s completely realistic. Look up the term “density altitude”. 

I agree, but there were several discussions about mixture issues of MSFS prop planes in the MSFS forum.

https://forums.flightsimulator.com/t/mixture-issues-with-prop-planes/273671/115

contains several profound contributions,

7 hours ago, Dominique_K said:

These days, I fly the 172 with glass panels.

It seems that she cannot go faster than about 103 knots IAS at cruise. I generally fly at an altitude between 5500 to 8500 feet with the engine running at 2400 RPM and the mixture set at a little less than peak EGT.  Flaps are up, of course. 

I am not familiar with the 172. In P3D I had the A2A 182 and the Cherokee not the 172. 

Is it that the modelling is wrong (underpowered) or that I do not do something right ?

You are looking at indicated airspeed. True airspeed  will change with altitude and air density. There are a lot of variables that affect 172 cruise speed.

For example: 

- propeller type (cruise, climb,  neutral),

- wheel fairing (often we take them off for training as they

- engine condition (low compression over time)

- tear and wear (scratch paint, lose seal)

What you see on average is about right. Asobo represent 172 model with fuel ejected 180 hp or S model. There are many older 172 with 160, 150, 140 engine Lycoming, Continental and etc. There are also 172 with engine  retrofit modes like Penn Yan and so!

 

Source: I'm proud owner of 172. I also have instructed in many different type of  172 over the years 😎

Yes it is painfully slow, but shorter trips at low altitudes are nice with it, especially the classic version.

There is a mod that adds a STOL equipment and also increases the cruise speed a little:

https://flightsim.to/file/6571/c172-stc-210hp-stol-classic

https://flightsim.to/file/6039/c172-stc-210hp-stol-g1000

This mod made the C172 (classic) my favorite GA aircraft in MSFS.

 

I fly the classic and the 1000 alot. I find the speeds are accurate. I typically show 112-115 TAS in cruise. This would be correct. I like the airplane for low and slow sight seeing, no higher than 2000 feet. I have taken it across Canada though when the sim first came out and really enjoyed it. Right now exploring the UK with the G1000.

Edited February 25, 20215 yr by jpe828