A2A CoS B377 - Maintaining manifold pressure at altitude and ineffectual turbo lever...

[MrBenevolent 0]

Love love loving my B377, but having a few issues this week.

 

Starting to fly longer and higher now and discovering that (as expected) around FL150 that the manifold pressure drops off and it is more of a struggle to maintain a climb.

 

My understanding is that full throttle + auto-lean mixture in combination with pushing the turbo boost higher should counteract this drop?

 

What is strange then is that, with the Turbos and Eng station completely under my control, the Turbo boost level seems to have no effect at all on the plane. I can set it from Zero to full whack and notice no difference in Man Pressure, temps, performance or anything else.

 

All the turbo bypass/mode switches are set to Climb/Cruise and the overrides are all off, so it should be engaged. Turbo bleed is on, but I thought this needed to be on for the pressurisation system?

 

Even if I turn on the Engineer, he seems to do little to boost my performance! Am I just expecting too much from the bird at these heights...I thought she was good for a comfortable 25000 or so?

 

Any ideas guys?

 

Cheers!

 

 

(and yes, I know I should probably try the A2A forums...and I will if you guys don't come up with anything...I just shuddered at the thought of registering for yet another bloody forum. Besides, this place is my home now!)

[spesimen 135]

My understanding is that full throttle + auto-lean mixture in combination with pushing the turbo boost higher should counteract this drop?

 

i always use auto-rich during climb. i forget where i read this, either the manual or forums, but that helps keep the cyl head temp down at full power. auto-lean is more for the cruise efficiency.. are you at 170 knots? should be like around 2550rpm,50" pressure, 190-200psi..set power by the psi..

 

What is strange then is that, with the Turbos and Eng station completely under my control, the Turbo boost level seems to have no effect at all on the plane. I can set it from Zero to full whack and notice no difference in Man Pressure, temps, performance or anything else.

 

All the turbo bypass/mode switches are set to Climb/Cruise and the overrides are all off, so it should be engaged. Turbo bleed is on, but I thought this needed to be on for the pressurisation system?

 

that sounds weird. what do the turbo bearing temps show? they stuck on one value also?

i'd have to refer to the cockpit to say for sure but it sounds like it's setup correctly. perhaps a screenshot would prove illuminating.

 

Even if I turn on the Engineer, he seems to do little to boost my performance! Am I just expecting too much from the bird at these heights...I thought she was good for a comfortable 25000 or so?

i use the engineer a lot and he seems to set the tubos correctly without muich trouble.

 

and yeah you should be able to easily reach 24-25000 even at a full load. i routinely fly up to 30k without any problems.,

 

although generally i set my flight plan to 24/25, then 'get on the step' to get to 200knots IAS (see the manual, basically climb 500 feet above target altitude and then pitch down to gain speed and get past the aerodynamic drag bump) and then do step climbs to 26/28/30 or whatever.

 

but yeah if it's not having any effect at all maybe it's just bugged, do you have the latest versions/try reinstalling/the usual suspect fixes?

 

cheers

-andy crosby

[MrBenevolent 0]

i always use auto-rich during climb. i forget where i read this, either the manual or forums, but that helps keep the cyl head temp down at full power. auto-lean is more for the cruise efficiency.. are you at 170 knots? should be like around 2550rpm,50" pressure, 190-200psi..set power by the psi..

 

 

Trying to climb at about 300-500fpm at FL150 I am about 110kts, 2400rpm, 40" pressure and 170psi or so at full throttle and full turbo...

 

Cowl flaps and intercoolers are closed as is RAM air and carb heat is on - all my temps looks bang in the middle of the green...

 

Will have a play keep mixture at auto-rich then try a reinstall and then push up some screenshots if I am still having issues.

 

Thanks for the suggestions - appreciated.

[spesimen 135]

110 knots is way too slow!!! thats almost stalling!!! after takeoff you should be mainly focused on slowly increasing flaps and climbing slow to reach 170 before anything else - that is where the optimal climb is....maintain that and climbing is a breeze..

 

the 170psi is also way too low, for climb you want 190-200. the manifold pressure is just a guideline, it should be in the 45-50+ range and once that's good then adjust your turbos up so the psi is close to 200... as long as the MP is in the green you're cool...should never need to be close other than takeoff anyway...

 

the setting you're using of.40 is ok for cruise.

 

also for climbing the rpm you want just at the top of the green (about 2550), when you are climbing that gets you the raw power in there....2100 for cruise gets you nice fast effiicent speed once you're leveled out..

 

you can easily do 1000 fpm up to 15000 and beyond if you are at a 170knots speed. it really only gets sluggish above 20k but you can still get 500fpm up to 24000 or 25000 without any trouble, that's why it's kind of like the sweet spot for starting your cruise.

 

cheers

-andy crosby

[MrBenevolent 0]

Bwahahahahahaha!

 

Ok - where is the super embarrassed smiley?

 

:fool:

 

So...it turns out I completely failed to understand what side of the switch constituted "on" and "off" with the main turbo cut out switches. All of them were off!

 

No wonder I was struggling and my engines were freezing!!!

 

Once flicked to the correct position, everything surged up like it should...and I am fighting Cylinder head temps like a proper B377 pilot should.

 

Now I just need to read up and understand what the various fuel selector settings mean and when to use them in flight and I am making progress.

 

Thanks for your help Andy and apologies for wasting your time.

 

Cheers

 

[spesimen 135]

hahahaha!

 

awesome, glad you got it sorted.

 

ain't no waste of time...i'm always glad to talk about one of the finest planes in fsx...i was actually just perusing avsim during a long cruise with the 377 anyhow lol..

 

cheers

-andy crosby

[MrBenevolent 0]

...i'm always glad to talk about one of the finest planes in fsx..

 

Isn't it wonderful?!

 

I didn't think such a plane would ever have any appeal for me at all - I am so, so glad I took a chance and bought it. Even my beloved Turbine Duke is gathering dust in the hangar this last week or so!