Oil and radiator control = optimal engine performance?

[TomcatViP]

Yeah rads are inducing drag. The default's CoD FM is correct.

Of course if you are flying with some amount of side slip or at a low pitch you won't notice any difference

For the correct settings, don't forget that at low alt it would be more difficult to cool oil/glycol fluids in most situation -> the radiator opening would hence have to be wider (a strong point for cruising at alt )

@ Kein : you can reach easily 480/490 level with the E.

[VO101_Tom]

Originally Posted by TomcatViP

@ Kein : you can reach easily 480/490 level with the E.

490? How?

[TomcatViP]

I suspect a strong feel of disbelief in your words Tom

But anyhow I convinced myself to (re)write the answer :

Increase your speed by diving slightly at 5m/s. Once your reach 500+ (usually somewhere btw 520/540) level your nose and keep your trajectory straight with the utmost of attention. Your oil&glycol rads shld be nearly fully closed (at high speed the amount of airflow would be enough to cool your eng).

And Taaada ... Th's it Your speed will stabilize at 500 and then will very slightly decrease to 480/490.

Note that with a very shallow descent (what was authorized by international authorities for high speed record) you can keep 500 IAS deck (with something like 50m/min descent (150ft/min)

[keinmann]

I'll give it a try, Tomcat, but I'm not sure if I believe that is sustainable in truly straight n level flying.

Btw, my results came from me cruising at exactly 100m above the English Channel: damn near sea-level.

[TomcatViP]

Originally Posted by keinmann

I'll give it a try, Tomcat, but I'm not sure if I believe that is sustainable in truly straight n level flying.

Btw, my results came from me cruising at exactly 100m above the English Channel: damn near sea-level.

No it's not. If it was it wld not hve been called max speed but max cruising speed Heat will soon force you to open the radiotor.

[keinmann]

Originally Posted by TomcatViP

No it's not. If it was it wld not hve been called max speed but max cruising speed Heat will soon force you to open the radiotor.

Now I see what you're talking about. Yes, that's totally possible. I think Tom got mixed up because I brought up level flight first.

[VO101_Tom]

Originally Posted by TomcatViP

I suspect a strong feel of disbelief in your words Tom

Ok, i understand now. Yes, the current FM keep the energy, but i thought you can reach the 500 with pure engine power

[mop]

TomcatViP I have a quick question on "low pitch". Are you referring to prop pitch (fine)? I am noticing no difference on the Spit/Hurri with the raidator, but I am still learning the finer points of trimming for speed.

Hmmm... I also have a second question. Not sure about German aircraft but the Spit and Hurri don't have aileron trim. I am having the issue that I often have to use ailerons to fly straight and level with my slip & turn indicator is showing the plane is properly centered. But I do notice a definite increase in speed.

Am I doing something wrong?

[TomcatViP]

Originally Posted by mop

TomcatViP I have a quick question on "low pitch". Are you referring to prop pitch (fine)? I am noticing no difference on the Spit/Hurri with the raidator, but I am still learning the finer points of trimming for speed.

Hmmm... I also have a second question. Not sure about German aircraft but the Spit and Hurri don't have aileron trim. I am having the issue that I often have to use ailerons to fly straight and level with my slip & turn indicator is showing the plane is properly centered. But I do notice a definite increase in speed.

Am I doing something wrong?

Hi Mop,

to clear the situation ( ) I was there talking about the angle of the blade with the plane of prop rotation (= pitch).

In the 109, the needle indicating the prop pitch, turns counter clockwise. This is the trigonometric positive way in maths that means that an angle is increased by opening a wedge from the right to the left and decreased on the opposite way (clockwise). This is why (only my own opinion) the indicator in german plane is done that way. WHen the needle turn that way, it indicate that the angle of the blades is increased.

Obviously, it's natural to refer to hourly induication, like 11h30, 10h etc... but keep in mind that in fact it refer to an increase of the pitch.

So I was effectively talking abt a high drag situation where your prop turn at high speed without pushing air bckward = blocking the air from flowing => Drag.

Regarding the ammount of left/right stick needed to counter the rudder action, it's pretty normal. In most of the plane you will fly, rudder action induce a rolling moment that need oposite aileron to balance the plane.

It comes easily with the time. Just find a comfortable position where your hand's own wheights will suffice to create the small roll action needed.


I hope it helps.

[justme262]

The joy or levelling off from a dive at high speed with the radiators closed, the prop coarse and the engine purring at low rpm. You can hold onto that extra top speed for longer than if you had the engine screaming and the rads open.

I don't know exactly how much extra speed I really get, but it certainly sounds good