2 Hawker 800A Questions

[PA31Ho]

I'm curious why you typically start engine #2 first.

Also, the forward static plates and the right pitot tube is powered by PS2 (forward static plates w.o.w.). The left pitot tube is PE powered. Why would they only put the left pitot tube on PE power? You can't really get much information with just one pitot tube. And if you're in icing conditions and you lost PS2 you're pretty screwed.

Thanks in advance...

 

[Canucit]

Well for one thing the static plates are not heated on the ground and I think they carried the #2 start from the the original hawker with the viper engines
and the left pitot tube is on pe because its connected to the pic instruments ( for loss of power) and the right pitot tube is for the right side instruments and standby instruments
look up what instruments you have left with loss of power in the emergency procedures (ep 16)
Michael

 

[pilot error]

l pitot feeds l adc. r pitot feeds r adc. you can lose the right pitot and still have accurate data on the l.

 

[PA31Ho]

I understand left pitot tube for left side, right pitot tube for right side. However, with one pitot tube ONLY (PE power only, double gen failure) how can you get accurate information to the ADC 1 with just a left pitot tube and no static plates? That just doesn't make any sense to me. You will only get airspeed information. With no static plates, you won't get any altitude information. When your batt 3 runs dead, you won't have ANY standby instruments.

Doesn't make sense to me.

 

[Canucit]

Well I guess they assume that if you lose both gens you will be declaring a emergency and landing. but you do have a point, if you have to land in icing conditions and you are on emergency power, your static system could be cause for concern but keep in mind that you have three gens for the aircraft
Michael

 

[ruhroa]

there is always the back up answer which i heard many years ago.................... its cuse thats how the brits made it

 

[jet2work]

As I remember it has to do with the fire supression system. IIRC one set of the fire bottles are powered off of the #2bus while the other is on the hot battery bus. So if you had an engine fire you would have the ability to use BOTH bottles in one engine.