The A2A Simulations Community

Hi,

Is aircraft performance affected by coolant temperature alone? Maybe it is my imagination but with higher temps I seem to require higher power settings to maintain a given airspeed. It is most noticeable after level-off after takeoff (e.g. takeoff, temps are at 110, accelerate to 180 indicated and level at 2000 ft - as the temps fall I find I throttle back slightly to maintain 180 indicated).

If this is the case, why?

Best regards,
Robin.

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A2A/AccuSim. 'nuff said!

G'day Robin,

As I see it, there are a few factors at work here.

First, the Merredith type radiator provides a neutral drag/thrust relationship at cruising airspeeds and normal setting thus to get TO cruise, more power will be required than is proportional to overcome drag AT cruise. Accelleration is also not brilliant (verses power) in the Baby Spitifres and the overcoming inertia and getting settled at an airspeed will/should require a little less power once you are established "there". Likewise, the aircraft may appear to have settled but is still accelerating, quite slowly, leading to the need to reduce power a little when this becomes apparent.

I agree, temperatures that are high (short of damaging levels) should not have a great effect on power but you may get some slight pre-ignition which may rob a little.


When you say "maybe it is my imagination but...." I take it that the effect is fairly subtle? If not, then the above is unlikely to be the explaination. If we are talking 20% reduction in throttle after a couple of minute's cooling, without touching the radiator shutter..then something is amiss. Due to circumstances, I haven't flown 1.2 for more than an hour or so in total..beta or post release, I'm still flying 1.1 mainly but I will have a look and make any reports that need to be made towards 1.3, when it comes.


Darryl

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...Some say he never blinks, and that he roams around the woods at night foraging for Merlin parts...

Hi Darryl,


Yes it is. It is like the initial power reduction wasn't "quite enough".

Thanks for the explanation, and makes sense for what I'm seeing.

Best regards,
Robin.

_________________
A2A/AccuSim. 'nuff said!