747-200/400 Anti-ice de-ice
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747-200/400 Anti-ice de-ice
What does the 747 use for de-ice/anti-ice, I'm sure it has a heated windshield and heated engine inlets and a heated wing. Besides the windshield being electric, how is the rest heated? Bleed air or electric? what other ice systems does it have. Thanks for your help. As you can guess I'm getting ready for round two at Cathay.
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The nacelle anti-ice system uses engine bleed air to provide engine cowl inlet ice protection. it can be operated in flight or on the ground.
The wing anti-ice system provides bleed air to each wing. It's inhibited in flight when leading edge flaps are extended and on the ground.
In flight when WAI is in auto the system operation is automatic. It can also be oprerated manually when the WAI is ON. No anti-ice system on the tail section because it's not necessary.
P.S. ask those recruiters in HKG why they rejected my application.
A2B
The wing anti-ice system provides bleed air to each wing. It's inhibited in flight when leading edge flaps are extended and on the ground.
In flight when WAI is in auto the system operation is automatic. It can also be oprerated manually when the WAI is ON. No anti-ice system on the tail section because it's not necessary.
P.S. ask those recruiters in HKG why they rejected my application.
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AFAIK, the Nacelle Anti-Ice on the 744 is automatic or manual, but Wing Anti-Ice is manual only. Maybe that's why they rejected your app... 
On the -200 both Wing and Nacelle AI are manual only.
Bleed air supplies both systems on both airplanes.
No other anti-ice systems on either one.
On the -200 both Wing and Nacelle AI are manual only.
Bleed air supplies both systems on both airplanes.
No other anti-ice systems on either one.
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Don't tell me CX hired you, anyways, I don't know what manual are you reading but if you read Boeing FCOM page 3.20.3 paragraph 2 you will have a better understanding, you can even look at the panel (if you fly 744) and you can see that WAI selector have OFF, Auto and ON positions.
Actually, the AUTO functions are options on both NAI and WAI on the 744. Man only on the Classic AFIAK. The WAI on both isn't inhibited with the slats out. It still works, but the hot air doesn't get to the LE devices so it's ineffective. So the advice is don't bother.
The tail leading edges aren't de-iced.
Good luck with part 2.
The tail leading edges aren't de-iced.
Good luck with part 2.
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I don't know what manual are you reading but if you read Boeing FCOM page 3.20.3 paragraph 2 you will have a better understanding, you can even look at the panel (if you fly 744) and you can see that WAI selector have OFF, Auto and ON positions.
I'm reading the manual for our 744s. No Auto on the WAI; yes Auto on the NAI.
I flew the 744 until a year ago; now on the -200.
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Let's think like a Brit
I made it to the first interview at CX and *then* got rejected.
If you're a Yank, I don't know what to tell you. Good luck, 'cause you're gonna need it. You gotta think like a Brit so I'd also add "Probe Heat" (pitot, static, TAT probe) to the list of anti-ice equipment.
The probe heat switches are positioned to 'on' just before pushback but it's not 'activated' until the nose wheel lifts off the ground (nose gear ground safety relay opens...)
If you're a Yank, I don't know what to tell you. Good luck, 'cause you're gonna need it. You gotta think like a Brit so I'd also add "Probe Heat" (pitot, static, TAT probe) to the list of anti-ice equipment.
The probe heat switches are positioned to 'on' just before pushback but it's not 'activated' until the nose wheel lifts off the ground (nose gear ground safety relay opens...)
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You are all correct
The golden rule in a 747, is once you have seen one 747, you have seen one 747. So no use arguing over Auto/On, some classics have Auto for Wing, some don't. Same for the 744. Apparently Boeing has stopped allowing so many options on newer acft. So play nicely.
spanner...I'm sure someone once told me the tip of the spinner was flexible - and hence any ice build up was shaken or wobbled off 
.......tell me I've sadly mistaken and it's more high tech
.......tell me I've sadly mistaken and it's more high tech
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Wiggy,
Sorry mate - RB211 spinner de-icing is definetely 'low-tech'
Sorry mate - RB211 spinner de-icing is definetely 'low-tech'
Spinner
The Spinner is such that ice build-up is not a problem.
The shape of the spinner was found to form a ring of ice about half
way back and this ring continuously broke off in small pieces,
preventing any imbalance. The small peices of ice are easily handled
by the L.P. compressor.
The Spinner is made of glass reinforced plastic with a coating of
polyurethane with a rubber (silastic) nose bonded to the spinner. If
ice forms on the nose section, it wobbles and dislodges the ice
before it builds up.
The Spinner is such that ice build-up is not a problem.
The shape of the spinner was found to form a ring of ice about half
way back and this ring continuously broke off in small pieces,
preventing any imbalance. The small peices of ice are easily handled
by the L.P. compressor.
The Spinner is made of glass reinforced plastic with a coating of
polyurethane with a rubber (silastic) nose bonded to the spinner. If
ice forms on the nose section, it wobbles and dislodges the ice
before it builds up.
The spinner must be changed if the rubber nose is damaged or
missing.
The temperature rise of fan air is sufficient to keep the inlet of the IP
Compressor clear of ice.
missing.
The temperature rise of fan air is sufficient to keep the inlet of the IP
Compressor clear of ice.
"You are all right". Yes, I agree. For a pilot interview, surely you can only
be expected to list the major systems. In addition, for full points, you can
add pitot/static probes, total air temp probes, angle of attack vanes,
heated windscreens (the main reason for heating these is that it increases
the impact strength of them) and you can throw in drain masts, water
supply/drain lines and you could even be so bold as mention to the
interview panel that the toilet service/dump cap has a heater blanket
fitted (saves having to chip off frozen poo). If anyone really wants to
know the in's and out's ofeach of these I can post the details.
be expected to list the major systems. In addition, for full points, you can
add pitot/static probes, total air temp probes, angle of attack vanes,
heated windscreens (the main reason for heating these is that it increases
the impact strength of them) and you can throw in drain masts, water
supply/drain lines and you could even be so bold as mention to the
interview panel that the toilet service/dump cap has a heater blanket
fitted (saves having to chip off frozen poo). If anyone really wants to
know the in's and out's ofeach of these I can post the details.
Do you really want to go the extra mile ???? How about APU inlet anti-icing?
General
An APU Air Inlet Anti-icing System using APU Bleed Air is
provided to prevent formation of ice on the APU Inlet Guide Vanes,
Inlet Duct Surfaces and APU Air Inlet Screen. The formation of ice
on the screen, and its subsequent release could cause the same type
of damage as any hard object ingestion.
An APU Air Inlet Anti-icing System using APU Bleed Air is
provided to prevent formation of ice on the APU Inlet Guide Vanes,
Inlet Duct Surfaces and APU Air Inlet Screen. The formation of ice
on the screen, and its subsequent release could cause the same type
of damage as any hard object ingestion.
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Thanks for all the help guys, to summarize the systems:
1) Heated leading edge, wing only (bleed Air) no tail?
2) Heated Inlets (Bleed Air)
3) Electric Windshield heat.
4) Electric Pitot/Static probes
5) Electric angle of attack/stall warning
6) Toilet service/dump electric heated
7) APU inlet heated (bleed Air)
8) Engine spinner (inertia)
1) Heated leading edge, wing only (bleed Air) no tail?
2) Heated Inlets (Bleed Air)
3) Electric Windshield heat.
4) Electric Pitot/Static probes
5) Electric angle of attack/stall warning
6) Toilet service/dump electric heated
7) APU inlet heated (bleed Air)
8) Engine spinner (inertia)
