King Air Brake De-Ice clearity

[skysurfer76]

Q1. Anyone know if a king air b200 can x-feed bleed air to the brake de-ice ? the schmatics and other readings are not clear.The AFM does mention not to use brake de-ice when single engine...

Q2. looking for a good King Air Forum....any sugestions?

 

[JAFI]

As I recall (and I don't bet the farm on my memory), brake de-ice was not standard and could be a modification (mod) - maybe or maybe not a Beech product. The aircraft should have the product information (a supplement or appendix) in the Airplane Flight Manual and in the maintenance paperwork. Not all mod's are the same, be careful in how you operate without the correct info. It can get real costly to repair.......
The Citation had (2) 3 inch ringed binders with just the Cessna mods. I had no Idea how many other companies mod's there were. So when you ask how something works make sure it is the device you have in your aircraft.

 

[340drvr]

Interesting question........no way to "manually" crossfeed bleed air through switches or such. Reviewing schematics, left and right bleed air plumbing has check valves on either side, assuring most pneumatic systems continue to operate if one side or the other fails (engine-out, bleed air line failure), but it appears that the "tee" to the brakes is upstream of this check valve, so it doesn't look like the brake de-ice bleed air would get to the failed side.
The single-engine limitation against using brake de-ice is probably simply to retain maximum horsepower in the (operating) engine.

 

[skysurfer76]

i agree with what your saying both of you ( JAFI and 340DRVR)

the suppliment section of AFM only mentions not to use duing SE, assuming like what you said (340) to maintain may power from operating engine...

the schematic does show that the L/R regulated (18psi) bleed air does go to a common manifold, but looks like check valves are at that location blocking a x-feed?

I'll keep diggin' thanks guys.

 

[JAFI]

So you are saying this is a Beech brake de-ice system and not some other manufacturer? Also be careful with "pilot" system diagrams, they are simplified for us simple people (non mechanics). The maintence diagram is usually more correct because the mechanic may need to "re-pipe" and need a correct picture to do so.

 

[deadstick]

The break deice is raw P3 air and not 18psi. As 340 mentioned, the check valves do prevent "cross feed" and the system is a HUGE drain on power when single engine (hence the limitation).