If the crew bag weight matters, then shouldn't babies? And carry on baggage? I find it amusing to hear gate agents and pilots discussing getting as many pink tag bags in the cabin as possible so that we are not over weight. It's a shell game, but only the CA will ever be blamed.

 

we did some quick calculations in the mx gate office just now and -80lbs of flight kit moves the cg about 1"... we sent an email to the manager of inspection... ball rolling ftw.. lol

 

When I was on the 200 I was taught to deselect the ground power switch prior to it being plugged in or removed because it had the potential to short out. Makes perfect sense with the amount of power being applied. When I moved to the 900 almost every pilot has said to leave the switch in because the 900 does not have the same "problem" as the 200.

I'm on the side of the MX guys here. If ground power is applied to the aircraft the switch should be deselected until you are ready to use it. I've ran into so many issues with bad ground power that causes the computers to go nuts and random stuff starts failing; and just like magic, if you power cycle the airplane it's fixed.

 

The 900 has left that switch in since 07 when I started flying them. Some of the older mesaba guys can speak to the 200 in msp i would think.

If this procedure is so awful for the plane and the ramp crew, then you should have no problem proving it on historical data.

Furthermore, as an ex rampie, the plug is attached and THEN power is added. While the giant isolated plug covered in rubber is worked in and out of the plane sometimes by a careless rampie or two with power applied, theres little chance of that AC power arcing to hands.

Is it possible Pinnacle guys made something up and DTW MX guys on here are simply echoing it because they fail to remember the jetbridge supplied powercarts are garbage? No other airport in the country has been able to fry a crj like the worthless airport authority provided external AC.

I like the 480VAC story though, can we get more of those tall tales in the future?

 

As you are saying here, you have more chances of getting shocked plugging in your toaster at home than AGPU power to the plane while standing in a puddle of water. Those plugs have some SERIOUS rubber on them.

As for the continued debate on power messing up the plane...

When you plug in ground power, it sits at the receptacle if the switch is out, going nowhere. If the switch is in (either because you push it now or it was left in prior), where does the power then go? To the GCU. Where it is tested and monitored. If the phase rotation is correct, and the voltage and Hz. withing required ranges, and if the dual current transformers inside don't detect a spike in amperage (feeder fault or "short"), THEN the GCU allows power to go to the plane.

Now, it's true that a split second of power application is required in order for the current transformers to detect the feeder fault; electricity HAS to flow for there to be a "short" detected. But again, whether you push the switch in after power is applied, or the switch is already in, the same thing happens.

Basically, all that switch does is keep ground power away from the GCU, not the airplane. If you plug in "bad" power, the GCU SHOULD, in most cases, do its job and protect the plane. But you as a button pusher have no idea if said power is good or bad when you press the switch, and the same thing will happen either way. The GCU works about 1,000 times faster than your finger can, and either saves the plane or fails.

And the only power that is applied to the plane is 115V, 3 phase 400 Hz. Enough so that if you DID get hit by it, it would get your attention. Having been shocked at least 10 times in my career, I can honestly say it's the most fun I never want to have again, but it's not the end of the world.

Back to my original issue with this new switchology... I have been taught since day one to push the switch out to agree with condition. If the company wants us to do something different, it needs to be in writing, not just coming from LCAs as we fly with them. Supposedly, this new switch thing has been out for months, and I only heard about it last month.

 

I'm gonna go ahead and listen to the a&p here, my dad is one st O'Hare so maybe I have a little bias but I'll gladly tell a Lca that I think the mechanic knows a little more about what he's talking about than him. I hear the word danger, or don't do it from them, That's all I need. End of story for me.

 

Power goes to the GCU to be tested whether the switch is in or out. That's why you get a green light. The power is not applied on aircraft until switch position is met and the GCU continues to show good power.

We've all had this happen before: power shows good, but the airplane won't take it. The avail light is on... why didnt that work? Let me do it again and see if I can see what's happening? Why is it showing green and it won't take it? Because the external AC can't produce any load, any current, any of that good sweet fry my nuts if i held on with both hands lovin. Ive seen guys conflate that with some sort of extra check the gcu is doing once pushed in.

On the 900 very little on the electrical has ever been about matching switch position. The gens stay on and are "dusty" regardless of power on ac. The 200 doesnt because that stupid system will keep power on clear below 18v, sometime after 10 or 5v it finally kicks the bad power off. The 900 ac has always been left in while plane is in use, only upon complete shutdown would it go off, which is different in the 200. In effect the 900 and 200 are the same on that one part, so to bring the fleet into conformity theyd like the switches to have the same procedure.

Nothing in the book has changed, but training has been told this is happening so get used to it. I wish they'd just change the books and then do it, rather than half the pilots doing one thing and the other doing another.

 

No, the book is the end of the story, and if there is some disagreement you consult the manufacturer. This aint pinnacle, we arent going to take the uneducated word of MX and whatever goofball self aggrandizing moron we hired from bombardier who was once a test pilot to make our books. We flushed that crap down the toilet where it belonged. This is 121, not the southern Minneapolis flying club, nor is it the northern Mississippi flying club.

Follow your books, LCAs might have the heads up on something coming down the pipes, but until that book change happens do what the fed would expect you to do on the jumpseat.

 

My personal feeling is that on the 200 losing 80 or so pounds in the nose may mean the difference of getting a jumpseater on or not. Or at least not needing several hundred pounds of ballast in the back for a 190 pound jumpseater.

 

That's not a feeling, just math. While you may still need balast, it would be less, perhaps a single hundred.