No APU....

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WBI Flyer

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Groundhog
Sitting on a B717-200. ... waiting to push back and the pilot comes on and lets us know that this aircraft doesn't currently have a functional APU, so they will start the enginges at the gate... blah bla blah.

hmmm.... I'd like an APU on our flight. Is it a big deal on 717-200s?
 
No Apu..????

Manjula and the octuplets will be sad.....

185


185
 
Many larger airplanes need an APU or a huffer (unit for ground start). The batteries are not powerful enough to spin the engine.
 
Not a big deal. Just a bit of a PITA for the pilots, and possibly uncomfortably warm for pax and crew while at the gate if the ground air sucks (which many times it does).
 
WBI Flyer said:
Sitting on a B717-200. ... waiting to push back and the pilot comes on and lets us know that this aircraft doesn't currently have a functional APU, so they will start the enginges at the gate... blah bla blah.

hmmm.... I'd like an APU on our flight. Is it a big deal on 717-200s?
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Why would you like one on your flight if you do not know if it is a big deal or not???? Makes no sense.

And no, it is not a big deal.
 
They might start one at the gate and cross bleed the other. Sit back and enjoy your flight.
 
I know our company 737 can't even be towed, except under emergency conditions with a dead APU.
 
WBI Flyer said:
Sitting on a B717-200. ... waiting to push back and the pilot comes on and lets us know that this aircraft doesn't currently have a functional APU, so they will start the enginges at the gate... blah bla blah.

hmmm.... I'd like an APU on our flight. Is it a big deal on 717-200s?
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Meh, if the MEL list allows it--no big deal! Get another drink!
jordane93 said:
I get the APU cranking as soon as possible.
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+1 get that air conditioning going!
SkyDog58 said:
Plus they don't have electric starters except on the APU.
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True on the 717 Rolls engines, but that is a broad statement that doesn't cover all models.
 
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If you have ground power (and expect to have it where you're going), it's not a big issue. There was a crash up in Canada of a plane dispatched without APU that ended up in a location that had no ground equipment and needed to deice but they were reticent to shutdown the engines as they had no way to restart them. They decided not to deice as you couldn't deice with the engines running. Suffice it to say, it didn't go well.

Oops.. that wasn't a DC-9/MD80/717 but rather a Fokker F-28. Same idea though.
 
The only ones that I know of with electric starters (in recent memory) is the BAe 146.
 
Tarheelpilot said:
I'm not aware of any transport category aircraft that have electric starters. Do you know of any?

Just curious
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Transport category.... 787 GENX engines use an electric starter, probably the only one that size.
 
jordane93 said:
I get the APU cranking as soon as possible.
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Unlike the CRJ2, basically everything else doesn't really need the APU on the ground once the engines are running. They are sufficient for cooling on the ground most of the time.

Hell, assuming the 717 is like the DC9, you can't even use APU bleed air in flight.
 
It's going to be a huffer cart kind of day.... Hope that the rampers know how to work the cart. "Which hole does it go into?....."
 
flyingron said:
The only ones that I know of with electric starters (in recent memory) is the BAe 146.
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flyingmoose said:
Transport category.... 787 GENX engines use an electric starter, probably the only one that size.
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The 787 is surprising. That's a big engine to crank on an electric motor. Had no idea about the 146 either.
 
KSCessnaDriver said:
Unlike the CRJ2, basically everything else doesn't really need the APU on the ground once the engines are running. They are sufficient for cooling on the ground most of the time.

Hell, assuming the 717 is like the DC9, you can't even use APU bleed air in flight.
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On the 727 the apu could only run on the ground. Well it could run in flight but it would start a fire.
 
WBI Flyer said:
Sitting on a B717-200. ... waiting to push back and the pilot comes on and lets us know that this aircraft doesn't currently have a functional APU, so they will start the enginges at the gate... blah bla blah.

hmmm.... I'd like an APU on our flight. Is it a big deal on 717-200s?
Click to expand...

No.
 
Tarheelpilot said:
Why?
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APU running and it takes a 5 man crew as long as we are not in congested areas on our facility, since they can use aircraft brakes. The one hangar it will fit in, while fueled, requires a 12 man crew to tow it to. Because of space limitations, not only do they have to have the apu running, but it requires wing and tail walkers along with chockwalkers at each wheel. There are a couple of places on the 1/2 mile tow that there is less than 3 feet of clearance on one wingtip.

Of course, it's not exactly a stock 737.....
http://www.codeonemagazine.com/article.html?item_id=50
 
Tarheelpilot said:
I'm not aware of any transport category aircraft that have electric starters. Do you know of any?

Just curious
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I am now totally confoozed. I thought the APU in the tail provided A/C and electricity to the cabin while boarding and then sent the "magic juice" to the electric starters on the main engines. Or does the APU provide bleed air to start the mains?
(disclaimer, I am not an expert on airliners, hence my dumb question)
 
WBI Flyer said:
... the pilot comes on and lets us know that this aircraft doesn't currently have a functional APU, so they will start the enginges at the gate... blah bla blah.
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Why did they even have to announce it? Imagine how many dumb pax will start panicking because the airplane is missing a dang APU. *rolleyes*
 
BigBadLou said:
I am now totally confoozed. I thought the APU in the tail provided A/C and electricity to the cabin while boarding and then sent the "magic juice" to the electric starters on the main engines. Or does the APU provide bleed air to start the mains?
(disclaimer, I am not an expert on airliners, hence my dumb question)
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Correct. It does a few things and bleed air for start is one of them.
 
Craig said:
APU running and it takes a 5 man crew as long as we are not in congested areas on our facility, since they can use aircraft brakes. The one hangar it will fit in, while fueled, requires a 12 man crew to tow it to. Because of space limitations, not only do they have to have the apu running, but it requires wing and tail walkers along with chockwalkers at each wheel. There are a couple of places on the 1/2 mile tow that there is less than 3 feet of clearance on one wingtip.

Of course, it's not exactly a stock 737.....
http://www.codeonemagazine.com/article.html?item_id=50
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I can see wanting brakes available for that kind of tow. Thanks for the reply
 
BigBadLou said:
I am now totally confoozed. I thought the APU in the tail provided A/C and electricity to the cabin while boarding and then sent the "magic juice" to the electric starters on the main engines. Or does the APU provide bleed air to start the mains?
(disclaimer, I am not an expert on airliners, hence my dumb question)
Click to expand...

APU has an electric starter, engines are all started using bleed air on engines this size. (Except the 787 and Bae 146 as someone else mentioned.)
 
ARFlyer said:
It's going to be a huffer cart kind of day.... Hope that the rampers know how to work the cart. "Which hole does it go into?....."
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More importantly:

Are the TIRES INFLATED on the cart? In my experience, that is the usual determining factor on how long it will take.
 
WBI Flyer said:
Is it a big deal on 717-200s?
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Like everyone else said, no it's not a big deal on a 717. On two-engine, long-haul aircraft, like the 777, A330, etc. not having a functional APU may have ETOPS considerations and may require a reroute, extra fuel, etc.
 
BigBadLou said:
Why did they even have to announce it? Imagine how many dumb pax will start panicking because the airplane is missing a dang APU. *rolleyes*
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Because it tends to get hot and sticky in the cabin in the time period between the ground AC duct disconnection and both engines running.
 
The DC8 never had an APU (other than a very few that had them added for private operations). Every flight required a huffer cart for start of at least the first two engines. Also a PC Air (Pre-Conditioned) cart for cabin heating/cooling. All in additional to the standard GPU or gate-power. It took a small army of ground support to operate that airplane.

One reason you'd mention the situation to the passengers is that the huffer carts are typically pretty loud and starting an engine at the gate is rather unusual.
 
Larry in TN said:
The DC8 never had an APU (other than a very few that had them added for private operations). Every flight required a huffer cart for start of at least the first two engines. Also a PC Air (Pre-Conditioned) cart for cabin heating/cooling. All in additional to the standard GPU or gate-power.
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No kidding? Very interesting!

And yeah, I'll tell the passengers if we start an engine at the gate. I might not mention an inop APU, but I usually make a comment when we do something a little different than normal, and starting at the gate falls under that. That said, I've done this exactly once in the last six years.
 
ARFlyer said:
It's going to be a huffer cart kind of day.... Hope that the rampers know how to work the cart. "Which hole does it go into?....."
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Was in DFW w/ an APU deferred. 3 carts later finally got 'em started (the engines).
 
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kgruber said:
The APU quite probably can't even be used in flight.
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Lose an engine generator and most checklists have you starting the APU. If an engine generator is deferred most APUs have to be run also, all for that APU generator.
 
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