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MD_Wild_Weasel
04-09-2011, 07:53 AM
Is the blenhiem torque to much? I cant seem to get her to go in a straight line! Full left brake and full left rudder and she still almost full circle to the right.. :o. Using single mission. Unless im doing something wrong its impossible to keep her on the runway.

mattag08
04-09-2011, 08:06 AM
Not saying the behavior you're seeing is accurate, but try this. First, throttle up only about 50% and allow the Blenhiem to get rolling. If you can keep it going straight, slowly add throttle till you can't any more. As you pick up more speed, you should be able to add more and more throttle due to the better rudder authority at higher speeds. This requires more runway, but should allow you to depart safely.

Lixma
04-09-2011, 08:07 AM
Check the rudder (in external view). I'm not sure if the patch fixed it but i've found that the Blenheim (and He-111) come with the rudder displaced to the starboard by 5/10% and needs trimming out.

MD_Wild_Weasel
04-09-2011, 08:11 AM
o.k just done a test. i took off with port engine(left i think :) ) at <25%> starboard engine at 100% with full left rudder and intermitantlty pressing the brake to keep her staright.
took a ntrk. but need to convert it

Furio
04-09-2011, 08:40 AM
Consider that a safe take off in a twin requires reaching Vmc before rotation, Vmc being the minimum speed at which the plane is controllable with one engine out (and with critical engine running).
Vmc is usually significantly higher than rotation speed you use in a single engine plane with comparable wing loading and stalling speed. The same is true for landing, in the event of a go-around. If the number is unavailable, you can use a common sense approach: rotate the plane no slower than 1.3 times the stalling speed, and do the same for flaring on landing. All of this agrees well with mattag08 suggestions. Landing and taking off in a multiengine are always critical and require extra cautions.

bando
04-09-2011, 08:40 AM
You did not brake your engine?
You actually took off?
Please tell me how.
I always break her engines halfway the runway, even running them at 80%

MD_Wild_Weasel
04-09-2011, 09:11 AM
You did not brake your engine?
You actually took off?
Please tell me how.
I always break her engines halfway the runway, even running them at 80%

yeah ive done it once using CEm but not with heat managment. I fought to keep it not crashing it into a building and let it go cross country. A hill gave me a little boostin take off.! LOL. One and only time...

Psycho_Ch!cken
04-09-2011, 10:19 AM
I actually think there's something wrong with that mission, assuming you're talking about the quick mission "Cross Country".

The Blenheim is turning all on its own when you spawn in. Only locking the brakes will hold it steady. As a test, I switched it to a Tigermoth to see what would happen. Result? The bloody thing still turns on its own. It's not left or right though, it's just towards a certain direction on the map, like there's some giant magnet there. And it only applies while you're on the ground, as soon as you get airborne, it all behaves, but try coming back in for a landing...

Something's definitely broken. I landed the Tigermoth, parked it, turned off the engine and the aircraft was still rotating all on its own.

I have the same problem with the Hurricane too on the "first solo" training mission. It keeps getting sucked to the left while you're taxiing, almost more than the rudder can correct, then to the right when you finally swing it 180 onto the runway. It's bizarre.

robtek
04-09-2011, 10:24 AM
If it turns always in one direction, even with different planes, then my bet is that is where the wind is coming from.
Those taildraggers always try to point into the wind, so it is pretty difficult to start with crosswind.

Furio
04-09-2011, 10:41 AM
If it turns always in one direction, even with different planes, then my bet is that is where the wind is coming from.
Those taildraggers always try to point into the wind, so it is pretty difficult to start with crosswind.

Consider also that taildraggers are inherently unstable on the ground. They were somewhat tamed in Il2, and probably they’re more realistically modelled in CoD. Taxi a real life taildragger is often more difficult than flying it, and can’t be done beyond a certain crosswind component. For this reason, WWI aerodromes were round, and nose-wheel gears are today standard for trainers.

huckster
04-09-2011, 01:40 PM
I actually think there's something wrong with that mission, assuming you're talking about the quick mission "Cross Country".

The Blenheim is turning all on its own when you spawn in. Only locking the brakes will hold it steady. As a test, I switched it to a Tigermoth to see what would happen. Result? The bloody thing still turns on its own. It's not left or right though, it's just towards a certain direction on the map, like there's some giant magnet there. And it only applies while you're on the ground, as soon as you get airborne, it all behaves, but try coming back in for a landing...

Something's definitely broken. I landed the Tigermoth, parked it, turned off the engine and the aircraft was still rotating all on its own.

I have the same problem with the Hurricane too on the "first solo" training mission. It keeps getting sucked to the left while you're taxiing, almost more than the rudder can correct, then to the right when you finally swing it 180 onto the runway. It's bizarre.

i agree, i've been messing with this mission for some time, AC always tends to rotate clockwise all the time until it aligns to specific point, i tried doing a 180 and heading into a tail wind, that does'nt work either.
i've tried tweaking engines and brakes and that doesn't work.

and to top it all off when you do finally manage to get it up, the split second you hit 1000ft it bugs and slams you into the dec.

MD_Wild_Weasel
04-09-2011, 02:59 PM
sounds a bit disheartening doin all that hard work only to be "bugged out". Anyways i found this from an earlier post..
from Blackdog_kt


I tried the Blenheim after watching the videos, it does try to run away sideways

The trick here is not to slam the throttle. I think it yaws to the right, so you can also use some differential thrust by adding more power on the starboard engine. Advance throttles to a moderately high setting, for example -2 or -1 psi boost, then press shift F2 (at least if you are using the default key commands) to select engine 2 and give it maybe an inch of extra boost. This way your no.1 engine reads -2 to -1 and your no.2 reads -1 to 0 psi boost.

Just to clarify, these are measured relative to ambient pressure on a standard day, so zero boost is equal to the ambient pressure, or 1 Ata for the German aircraft or approximately 30 inches HG for US aircraft, or 760mm HG for the Italian ones. So, zero boost is by no means low power, it's actually full power minus the supercharger (that one can go above ambient pressure).

Anyway, once you do the above little trick with the differential thrust, kick the rudders in or add rudder trim and let it start rolling and pick up some speed. If you slam the throttles to the stops you'll get a whole lot of torque and no means to counter it.

However, if you let it accelerate to 20-40 mph before going flat out, there will be some airflow over the rudder to make it effective and you can also use differential wheel brakes if you really need some last moment corrections. The differential engine thrust is just meant to keep you pointing straight until you get to that speed.

After that, select both engines (default keys are shift ~) and gently push the throttles the remainder of the way. I usually don't trim the nose up until i've lifted the tail off the ground but your mileage may vary. Make sure you've warmed up to at least 40-50 degrees oil temperature so that the engines run smooth and the propeller governors work well, otherwise your RPM will be jumping all over the place and causing asymmetric thrust (radials are harder to start in cold conditions and take longer to warm-up due to being air-cooled).

Important: Turn OFF your carb heat before the take-off run. It's one thing to pre-heat them to help those air-cooled radials start, but leaving it on robs you of power: hot air is less dense-->you get less air density for the same amount of fuel-->it's like running on super-extra-lean mixture.

I tried starting up the Blenheim after watching the videos, did it fine and naturally i tried to take-off. I botched it because i didn't expect it to yaw that much but i was able to control it, even when improvising the above method on the spot. I didn't make it because i didn't want to restart the mission so i ended up clipping a wing on a hangar, but i did manage to keep it going straight and reach take-off speed despite the initial surprise.

I think that with prior knowledge of my failure and the conclusions from it you'll do fine
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meplay
04-09-2011, 06:45 PM
hey do you guys get fluctuation when throttling up?, the way i do it is i put full trim to the left then throttle right engine up full and right engine half way, but i still get bad tail drag :(