Commercial Flight Diversion - Loss of Navigational Capabilities?

jordane93 said:
Almost. About 1300 pounds/minute. It uses both center pumps to jettison fuel but it’s 1300 total. Not 1300 per each pump
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Well, maybe your fleet is different but straight from our systems manual.
“Two dual pump units provide a high capacity jettison rate of approximately 2600 pounds per minute.”
Maybe Boeing had different options available.
 
EvilEagle said:
Depends on where we are going, how much cargo/pax we have and what the weather forecast says (just like every other airline flight).

I've never flown the 777 but a quick search turned up this page: https://www.liquisearch.com/boeing_777/specifications

The biggest difference (that I saw) between max T/O and max landing weight was for the 777-200LR which I think was only flown by Delta (before we retired them) in the US. At any rate, that's about 274k# difference if it was max'd out. Another search gave me about 14k#/hr in cruise. We're burning about 28k#/hr in the 330 on takeoff so the 777 must be at least that. Ballpark you'd burn 130k# ish in 8 hours. So you could be overweight by a good bit and need to dump if you were in the worst case configuration and type of 777. Maybe it's worth it to be 30k# lighter? Unless we know more about the specifics it's all a guessing game. They probably had a good reason to dump - and maybe their company says they need to. Could be as simple as that.
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Thanks. The last is why I pointed out non-US carrier.
 
WDD said:
How can a modern airliner lose Navigation and Communications???
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Well, it could be designed by Boeing.... :devil:


I doubt they lost ALL comms and nav, but they probably were below the minimum required by airline standards to continue across the ocean. Losing a power bus could do it, for example if one item on the bus failed so as to put an excess load on the line and popped the breaker.
 
Heck - get those guys a subscription to Fore Flight (splurge for the premium offer) and let them fly off the I pad. Toss in a Sporty's PJ handheld, and good to go!! :cool:
 
Are airliners required to have HF radios for transoceanic flights?
 
WDD said:
Heck - get those guys a subscription to Fore Flight (splurge for the premium offer) and let them fly off the I pad. Toss in a Sporty's PJ handheld, and good to go!! :cool:
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Don't forget a homemade Stratux.
 
Half Fast said:
Are airliners required to have HF radios for transoceanic flights?
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Route specific. You can cross the Atlantic with VHF only but you have to take a route well to the north to stay within VHF range (Blue Spruce routes). All long-haul airliners will have multiple HF and VHF radios installed, though. Nearly all with have satellite-based CPDLC as well. If both of those fail, you have to ability to relay messages through other aircraft in the area on VHF as everyone is monitoring both oceanic air-to-air (123.45) and Guard.

I forgot, was this a 787?

The 787 has six generators (two per engine and two on the APU) so a lot of sources of power. Losing a BUS completely is relatively rare, as each BUS can be powered by multiple sources. Losing a BUS entirely usually means a rare fault (short) or failure in the BUS switching logic.

I don't have any specific information on the 787, but I have flown the 767 which would have a similar design philosophy, minus the 787's improvements.

The "big Boeings" (excludes the 737 and previous) have three independent navigation systems, each anchored by its own Inertial navigation unit (IRU). There are three flight management systems (FMS) which each have an independent set of data inputs (flight data computers and sources). Each FMS maintains its own position estimate and uses data from its respective IRU, GPS, and VOR/DME/LOC inputs to update its position. Each of the systems uses its own, separate power sources and each has varying levels of backup power.
 
Busflyer said:
Well, maybe your fleet is different but straight from our systems manual.
“Two dual pump units provide a high capacity jettison rate of approximately 2600 pounds per minute.”
Maybe Boeing had different options available.
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Yea our manual says rate of 1300 pounds per minute:dunno:
 
I was on a AA 757 DFW-ANC in 2009 that took a long delay after returning the gate while taxiing due to an IRU failure. And DFW-ANC isn't ETOPS and all that. I only remember it because it was the beginning of my honeymoon lol
 
I was on a 777, CDG to IAD. We had to stop and reboot the aircraft before take off.

Luckily the reboot fixed the issue.
 
It was a Boeing. And Boeing is in Seattle area. And MicroSoft in the the Seattle area.........
 
jordane93 said:
Yea our manual says rate of 1300 pounds per minute:dunno:
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Our 767’s were 2600 lbs initially but a change was required by Boeing for reasons I forget that reduced the rate to 1300 lbs. you can also only dump the center tank. It’s possible to be well over normal landing weight with just wing fuel. Been there and done that single engine.
 
Half Fast said:
Are airliners required to have HF radios for transoceanic flights?
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We are required by Op Specs to have HF and CPDLC; we can't go unless the latter is working upon departure. I've lost it a few times and had to revert to HF which is usually a result of lost signal.
 
When I see a departing aircraft, I never say "Have a safe flight.", I will say "Have a boring flight." I have had a few "safe" flights that were very "exciting" to say the least.
 
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