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Tord Hoppe
12-19-2004, 01:50 PM
Hi all, just wanted to check if anyone else is seeing this. I´m always starting with a default Cessna flight, then loading the DF727 in cold and dark setting. Following the checklists I see no pressure rise in the hyd brake pressure gauge when getting to the point where I turn on one of the "B" pumps and open ground interconnect switch (sorry, don´t remember the real name) that transfers the hyd power so that also the A system is pressurised. In other words, both A and B hyd systems are pressurised, but I get no brake pressure and am unable to engage the parking brake when the ckecklist states that I should do so. Does it matter wether the parking brake is on or off in the cessna prior to loading the DF727?
The brake pressure does come on after engine start, but I usually need to "wiggle" the toe brakes on my CH pedals and using the keys for the parking brake. This feels a bit weird which is why I wanted to check in here...

On another note, the oxy pressure gauges are constantly at zero for me. No biggie, just thought I´d mention it.

Cheers
/Tord

Paul Golding
12-19-2004, 04:51 PM
Thanks, I'll let Nick know.

petermcleland
12-20-2004, 07:27 AM
>
>On another note, the oxy pressure gauges are constantly at
>zero for me. No biggie, just thought I´d mention it.
>

I noticed that on loading the aircraft and going immediately to that panel, I see the Oxygen pressure gauges smoothly leaking away the pressure down to zero.

Olivier
12-20-2004, 09:28 AM
Hi,

I confirm, no oxygen here as well. The break pressure also is 0 until I started the engines and turned on the "A" hydraulic system, is that normal ?

Thanks
Olivier

skeating
12-21-2004, 08:54 AM
Yes, I don't have any oxygen pressure either. Definitly a "No Go".

I noticed a few other things about the hydraulic systems as well.

I know this is probably outside the limitations of FS but with the E.D.P.s switched OFF( only done for emergency and abnormal procedures, after start checks and maintainence as the pump depressuizing solenoid is electrically energised when switched off and it is not continously rated and could, will, burn out) the A system still shows 3000 psi with the Interconnect closed.

I thought this might be a good time to get some more info on the Hydraulic system

I am only guessing on this (educated guess mind you) from experience with Boeing and other manufacturers products (never operated the 727) and I could be totally wrong, but this is how I understand the system to work.

The Hydraulic Interconnect Valve only allows the B system to power the A system services, gear, flaps ,slats etc. on the ground for maintaince and preflight checking proceedures.
There is a check valve which prevents the A system from powering the B system services even with the interconnect open.

When the gear is retracted the A system Hydraulic Quantity Gauge should show a decrease in quantity of about a gallon and when the gear is extended the quantity should recover.

When the slats and flaps are extended there should be a reduction of about half a gallon, recovered when they are retracted.

The quantity should also decrease in the cruise due to cold soak.
I only mentioned these as possible background info and maybe someone might possibly try to add these features at some future date if FS would allow it.

I also can confirm that the brake pressure gauge does not seem to function correctly

What a great product, well done Dreamfleet.
Pretty soon I think I'm going to only have Dreamfleet products on my H.D.
A merry Christmas to Lou, Paul and all the rest of the team
Best regards
Steve

Paul Golding
12-21-2004, 10:47 AM
Thanks for the comments Steve. I doubt much of these will appear in the update - aside from fixed oxy and brake press. Future versions will evolve though, hopefully with even more random failures.