MiG-3 Overheat issue?

[6./ZG26_Klaus_Mann]

Going full force at 7500m I have to open water to 60% and more, while the Oil overheats with less than 50% Radiators. That way it is impossible to achieve more than 600kph even at that altitude. 

I don't know what's going wrong, but something definetly is. 

[Matt]

You didn't adjust the mixture i guess.

[6./ZG26_Klaus_Mann]

You didn't adjust the mixture i guess.

I actually did inform myselfg about how to mixture this aircraft beforehand. 100% for highest power output, I did vary it around, but above 6500 it didn't make a difference between 50% and 100%.

You can achieve 640, but then immediately your engine stops. 

I barly keeps cool at 75% water radiator. 

Edited December 22, 2015 by 6./ZG26_Klaus_Mann

[Nocke]

Hi there,

 

I am just starting to learn the Mig-3, and really amazed about the speeds you reach.

 

Summer map, 80% fuel, 7500m on gauge, 75% mixture, water radiator 75%, throttle and prop pitch 100% I do reach, on auto level, after some minutes 400kph indicated.

I guess your numbers are TAS, but on the only table I have (probably not quotable or reliable, no temperature dependence given, but it is what I have ...) that is said to equal around 580kph TAS.

 

Could you tell me how you convert IAS to TAS, resp. where you read the TAS from?

 

And, of course, perhaps give me a hint what I am doing wrong, why I am so slow?

 

 

Thx a lot!

[II./JG77_Manu*]

Hi there,

 

I am just starting to learn the Mig-3, and really amazed about the speeds you reach.

 

Summer map, 80% fuel, 7500m on gauge, 75% mixture, water radiator 75%, throttle and prop pitch 100% I do reach, on auto level, after some minutes 400kph indicated.

I guess your numbers are TAS, but on the only table I have (probably not quotable or reliable, no temperature dependence given, but it is what I have ...) that is said to equal around 580kph TAS.

 

Could you tell me how you convert IAS to TAS, resp. where you read the TAS from?

 

And, of course, perhaps give me a hint what I am doing wrong, why I am so slow?

 

 

Thx a lot!

only really accurate way is to use the grids as reference, set your plane to 0,90,180 or 270 degree, and then start the time when your nose touches the edge of a grid. then fly 4 grids (40km), to get a less then 1% timing error. Then you can calculate it

[Nocke]

only really accurate way is to use the grids as reference, set your plane to 0,90,180 or 270 degree, and then start the time when your nose touches the edge of a grid. then fly 4 grids (40km), to get a less then 1% timing error. Then you can calculate it

Roger. Did that:

 

7550m, 100% throttle and prop pitch, 75% oil and water radiator. Oil and water both end up close to 100° C, IAS at 396 kph. TAS calculated as 593 kph. Practically the same as OP.

Nice to be able to reproduce that and to know I am not doing anything wrong

 

Edit: wind and turbulence off...

Edited January 10, 2016 by Nocke

[II./JG77_Manu*]

Roger. Did that:

 

7550m, 100% throttle and prop pitch, 75% oil and water radiator. Oil and water both end up close to 100° C, IAS at 396 kph. TAS calculated as 593 kph. Practically the same as OP.

Nice to be able to reproduce that and to know I am not doing anything wrong

 

Edit: wind and turbulence off...

Ok nice. What season did you take? In case of summer, all the aircraft are slower because of the warmer temperature. In case it was autumn, it's still not necessarily "to slow"  

Keep in mind the following things: 

- Full throttle altitude is 7800m, that could make a difference

- top-speed test could well be with more closed radiators. I don't know the exact procedure for the Mig though.

- slat-version of the Mig was slower then non-slat-

from books i know even lower numbers.

But something is wrong. At ground level the Mig is faster then any real life production Mig, even the 640kph prototyp, and at altitude it's definitely on the lower side of the charts, meating the slat-mig performance charts from books/the link.

That doesn't fit together

Edited January 10, 2016 by II./JG77_Manu*

[Nocke]

It was on summer map. Actually for me everything is fine now.

My only concern was that at first I had the impression to be completely unable to reach the speeds Klaus_Mann gave at the beginning.

Now I know I reach the same ones and am not doing something completely wrong.

I do not care much about comparisons to real world perfomances - the plane I get here is the plane I get, just that, and I simply assume the developers are doing the best they can do in the time they have.

 

 

Edit: and sorry for derailing your thread, Klaus_Mann ....

Edited January 10, 2016 by Nocke

[1PL-Husar-1Esk]

I was flying mig-3 mostly at 80% mixture (without bost, radiators at 50-60%, prop 80%, throttle 100%), then i saw temperature icon and temp at 120 deg. at all gauges (was at 6km height). I opened fully radiators, reduces throttle and propeller pitch, dived and start to glide. But temp would not go down, my engine was damaged, so  i glided and land, was waiting in cockpit but temperature stays all time at 120 degrees.

Edited February 14, 2016 by 307_Tomcat