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Incident: United B757 at Newark on Jul 8th 2016, rejected takeoff due to generator failure

A United Boeing 757-200, registration N598UA performing flight UA-1979 from Newark,NJ to San Francisco,CA (USA), was accelerating for takeoff from Newark's runway 22R when the crew rejected takeoff at low speed reporting a generator failure (engine PW2037). The aircraft slowed safely and returned to the apron. ( More...

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Not too many years ago I was in an Air France B-707 at Orly airport taking off for Rome when shortly before V1 the power was shut down and the airplane came to a stop on the runway. The pilot then made a 180 back to the runway and tried again, this time we went airborne. No announcement as to why, no fuss. just a normal operation. So French.
That had to have been more than not too many years ago...
Che Jackson 2
Let's just put a line through the 'not many' part of your comment.
How astute you are to discern that it was more than "not too many years ago." How long ago do you think it happened? You may need a calculator.
It had to have been at least 32 years ago as Air France retired the 707 from their fleet in 1984.
Alan Brown 1
When it came to crew, just remember..."Always Look for the Union Label."

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joel wiley 4
It appears the quote is from a paper I found here:
and indeed, Mr. Tenning refers to the item as 'alternator'.
However, Chapter 9 of the FAA Airframe Handbook found here:
mentions that generators producing alternating current may be called either generators or alternators. Perhaps perusal of the FAA document can help you out.
cheers and happy reading.

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JetMech24 3
Just for your information, taken from a Boeing 737-700 Aircraft Maintenance Manual:


The electrical power system makes and supplies AC and DC power to airplane. The system has automatic and manual controls and protection. A standby AC and DC system gives normal and emergency power.

AC Power

The electrical power system has four main AC power sources and one standby power source. These are the main AC power sources and their supply capacity:

Left integrated drive generator (IDG 1) (90 KVA)

Right integrated drive generator (IDG 2) (90 KVA)

APU starter-generator (90 KVA below 32,000 feet/9,753 meters, and goes down to 66 KVA at 41,000 feet/12,496 meters)

External power (90 KVA).

The IDGs and APU starter-generator supply a 3 phase, 115/200 volts (nominal) at 400 Hz. The AC power system design prevents two sources to the same load at the same time.

The static inverter supplies a one phase, 115v ac output to the AC standby bus.

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Big airplane = generators
bentwing60 7
He might be just a step out of touch with the times and or the equipment.

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bentwing60 6
Is it possible that "you Peter F" might actually be mistaken? JMOH
ToddBaldwin3 3
No, I believe that is an impossibility.
Ruger9X19 5
First, the alternator is a specific type of generator that produces AC current through a rectifier and not a commutator.
As to the nuts and bolts of it There are two main mechanical parts to a generator the stationary part called the "ststor" and the rotating part called the "rotor". Both have conductors wound through them. There are electronically two main parts to a generator as well. The magnetic field windings, and the electrical generating armature windings. The armature can be either the rotor or the stator. Generally speaking an alternator uses the rotor as the field windings and the stator as the armature, thus the armature windings of the alternator are directly connected to the bridge rectifier and not through a commutator as in a traditional generator.
Most modern recip engine aircraft have a starter and a separate alternator, most turbine aircraft utilize a single unit starter/generator where the rotor has a commutator and is the armature.

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Ruger9X19 2
I will reiterate that an alternator is a generator. Further furthermore any system utilizing an alternator or generator is the power generator system.

I think I see your confusion you make the assumption that any AC generator is an alternator. In fact there are both AC and DC generators other than what is typically termed an alternator.

The IDG on an aircraft turbine engine makes use of a continuously variable transmission (also known as aconstant speed drive)which converts the variable input speed provided by an aircraft's engine into a constant output speed for the IDG's integral AC generator.

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Ric Wernicke 5
Carl writes in the manual for the 777 that power is supplied by generators. The APU has a generator and even the RAT has an AC generator.

Now for semantics. There is no one who calls a device that passes current in a single direction a "Transformer Rectifier." There is a "Transformer-Rectifier Unit (TRU) on the 777. Carl is correct, but your misreading of his writings is comical bordering on the absurd.
Tim Marks 3
The correct term is generator, since this failure occurred with the Integrated Drive Generator (IDG) on this aircraft. Alternators are used on cars and GA aircraft.

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JetDoc66 3
For the love of God Pete read this.

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JetDoc66 3
Pete, I'm a an A&P mechanic, ATP and a Captain at an airline. If during my next systems validation the check airman asks me what powers the A/C buses and I answer "alternator" I'm going to get laughed right out of the briefing room. Boeing's own maintenance manuals call it a generator. Just let this one go OK?
ToddBaldwin3 1
Quibble: To argue or find fault over trivial matters or minor concerns.

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You got serious issues...

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