Some Q's for Xjet ERJ Trainin

edmondfitzgerald

New Member
Some Q\'s for Xjet ERJ Trainin

What's a QRH? S'posed to verify this pub is in cockpit.
Why is a SHED bus a SHED bus? Does it "shed" somethin'?
What's a PBE? Personal Breathing Equip? and what is that?
Why only 5 life vests and not 55? Ferry flights? Explain...
Escape ropes in the cockpit for what? How?
Elevator and Aileron disonnects. What do they do and why?...Maintenance has to access rigging bay and recon torque tubes...sounds scarey. "Uh, yeah, sorry for pullin' the red thingy captain..."
tongue.gif

Reversionary panel. Huh? Deer in the headlights....
 
Re: Some Q\'s for Xjet ERJ Trainin

Well I don't work for XJT but these questions are more aircraft specific than airline specific, so as an ERJ driver I can answer most of them.[ QUOTE ]
What's a QRH? S'posed to verify this pub is in cockpit.

[/ QUOTE ]QRH is a quick reference handbook. It typically contains abnormal and emergency procedures checklists and should be in the cockpit at all times for ready reference in an emergency.[ QUOTE ]
Why is a SHED bus a SHED bus? Does it "shed" somethin'?

[/ QUOTE ]The Shed Bus is so named because the EDL (Electrical Distribution Logic ... brains of the electrical system) will "shed" (cut power to) this bus first in the event of an electrical emergency in order to conserve battery power. It contains items that are not flight-essential like galley power.[ QUOTE ]
What's a PBE? Personal Breathing Equip? and what is that?

[/ QUOTE ]Yes, personal breathing equipment. Basically a smoke hood combined with a portable oxygen generator. Designed to allow you to safely escape from the aircraft should there be smoke and/or fire present.[ QUOTE ]
Why only 5 life vests and not 55? Ferry flights? Explain...

[/ QUOTE ]The airplane is not approved for overwater flight beyond 50NM from the nearest shoreline. Hence, the idea is that the vests wouldn't be needed because by the time the airplane hits the ground, it'll be on terra firma. Besides, this isn't a bad thing. The yellow-orange color of the vests attracts sharks, anyway. A helpful hint ... give the vests to five passengers you don't like and use the seat cushions instead if you do wind up taking a swim.[ QUOTE ]
Escape ropes in the cockpit for what? How?

[/ QUOTE ]Because it's too long a way from the cockpit window to the ground to jump unassisted.[ QUOTE ]
Elevator and Aileron disonnects. What do they do and why?...Maintenance has to access rigging bay and recon torque tubes...sounds scarey. "Uh, yeah, sorry for pullin' the red thingy captain..."
tongue.gif


[/ QUOTE ]They disconnect the flight control cables from the yokes. Use them in the event of a jammed flight control, for example, or at any time called for by a QRH checklist.[ QUOTE ]
Reversionary panel. Huh? Deer in the headlights....

[/ QUOTE ]Switches your displays from primary to backup (reversionary) mode. Used when various systems involved with the glass cockpit displays fail.
 
Re: Some Q\'s for Xjet ERJ Trainin

[ QUOTE ]
Elevator and Aileron disonnects. What do they do and why?...Maintenance has to access rigging bay and recon torque tubes...sounds scarey. "Uh, yeah, sorry for pullin' the red thingy captain..."
tongue.gif


[/ QUOTE ]They disconnect the flight control cables from the yokes. Use them in the event of a jammed flight control, for example, or at any time called for by a QRH checklist.

[/ QUOTE ]

Can you elaborate on this some more? I envisioned a totally "fly-by-wire" system with no cables--just synchro/servo systems. Does the plane have physical connections between yoke and control surfaces? Am curious and confused. Was "assuming" completey without pulleys, cables, etc.... Thx... man....
grin.gif
 
Re: Some Q\'s for Xjet ERJ Trainin

Are you in ground school?
 
Re: Some Q\'s for Xjet ERJ Trainin

Wait to get all the nuts and bolts when you actually get in class. At most airlines, the only thing you should possibly be worrying about before you go is memory items and limitations, thats all! Dont try to jump ahead, stay with the flow and give each thing its due course. Its much like the NE Patriots looking at the next game only. Youll have time. If youre already in groundschool and dont know this info, then your way behind anyways and shouldnt be on the computer to begin with.
 
Re: Some Q\'s for Xjet ERJ Trainin

[ QUOTE ]
Can you elaborate on this some more? I envisioned a totally "fly-by-wire" system with no cables--just synchro/servo systems. Does the plane have physical connections between yoke and control surfaces? Am curious and confused. Was "assuming" completey without pulleys, cables, etc.... Thx... man....

[/ QUOTE ] I do not have specific knowledge of the RJ, but most 'small' aircraft do not have a full fly by wire system. Usually the only thing that would even have to be powered on a smaller aircraft would be the tail. For most of the flight controls the cables and pulleys work fine. It is only the tail that needs some type of power assist for the rudder. This can either by hydraulic, or cables and pulleys backed up by a rudder bias system that has a set of pistons plumbed into the engine bleed air system. (In an engine failure this bleed air powered rudder bias system will deflect the rudder toward the good engine. The rest of the time it just sits there not doing anything.)

The reason the tail must usually be hydraulic powered or augmented by some other system is that there is a certification requirement that the max rudder input be 150 lbs. in an engine out scenario.

Since RJ's are not very large, or very fast (*) they should not really require a full set of powered controls. If powered controls are required, FBW can save weight as there is less hydraulic plumbing required, but you can also do it the old fashoned way. It just depends on what the cert. requirements are and how much you want to spend to achieve them.

* Usually powered controls are used for 2 reasons:
1. The aircraft is very large and has large control surfaces. The pilots may not be strong enough to move the surfaces. On some of the largest piston powered aircraft like the B-36 which had ailerons the size of the wing on a B-17, the ailerons were actually 'free floating' and were not connected to the control system. The pilot's yoke was actually connected to a smaller servo tab on each aileron. This was a simple system, but the pilot did not have ailerons at slow speeds during takeoff or landing. Hydraulic controls solved this problem.

2.If the aircraft is very fast, shock waves forming on the wing can cause problems. This can take the form of control 'buzzing' ,very high control forces or even control reversal. Powered, non-reversing controls (controls that cannot be moved by aerodynamic forces acting on the wing) solve the problem.
 
Re: Some Q\'s for Xjet ERJ Trainin

[ QUOTE ]
Can you elaborate on this some more? I envisioned a totally "fly-by-wire" system with no cables--just synchro/servo systems.

[/ QUOTE ]You're welcome for the previous answers ... it's actually a good refresher for me to dust off the brain and review this stuff from time to time!

The ERJ is NOT a fly-by-wire airplane. The elevator is strictly cable-actuated. The rudder and ailerons are hydraulically-assisted. The closest we come to FBW technology is the engines, which are FADEC-controlled. There are no cables connecting the thrust levers to the engines ... electrons do all the talking, the FADECs give all the orders.

Kingairer is right ... if you're not in class yet, you shouldn't be worrying about systems in this much detail ... your excitement is admirable, but unnecessary. If you're already in systems, definitely take more time to review. Good luck.
 
Re: Some Q\'s for Xjet ERJ Trainin

[ QUOTE ]
They disconnect the flight control cables from the yokes. Use them in the event of a jammed flight control, for example, or at any time called for by a QRH checklist.

[/ QUOTE ]

K, somebody's gotta ask....what next? Just fly using the trim/natural pitching tendancies?
 
Re: Some Q\'s for Xjet ERJ Trainin

[ QUOTE ]


K, somebody's gotta ask....what next? Just fly using the trim/natural pitching tendancies?

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No, these disconnect the two control yokes. If one side jams, the other pilot can override the interlock and then disconnect the two yokes. At that point, only one pilot has roll control or pitch control, whatever may be jammed. At least that's the way it works on the SAAB, someone on the 135/145 correct me if I'm wrong.

The most fun thing I did in sim training with my current employer was giving us both pitch and roll failures in the separate yokes. That was an excercise in CRM. We managed to get it on the ground, too.
 
Re: Some Q\'s for Xjet ERJ Trainin

[ QUOTE ]

The most fun thing I did in sim training with my current employer was giving us both pitch and roll failures in the separate yokes. That was an excercise in CRM. We managed to get it on the ground, too.

[/ QUOTE ]

well that's not hard, i can get anything on the ground....now on the ground in one piece is an entirely different story ;-) Thanks for the answer :-P
 
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