highflier92660
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A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sat Dec 08, 2007 2:47 pm

One of the enduring topics on anet is the westbound range problems that plague JetBlue. Often I log on to flightaware.com and compare UAL 177 and JBU 637, a Boeing 757 and A320 that leave Boston Logan within minutes of each other and fly to SFO. More often than not the 752 blocks in 10 to 15 ahead of the A320. Not yesterday.

http://www.flightaware.com/live/flig...7/history/20071207/1609Z/KBOS/KSFO
http://www.flightaware.com/live/flig.../history/2007/1207/1607Z/KBOS/KSFO

The two departed BOS within two minutes of each other, United at 11:07am and B6 at 11:09am. They flew the same SID with United initialing FL 360 and B6 at FL340. From that point on there was a divergence of roughly 20 knots plus across the country as they both went north of a howling west-to-east jet core. The United aircraft never asked for higher while the A320 burned off to FL360 then FL380. As they flew over southern Idaho B6 at FL380 was clearly ahead with the United 757 slightly south and closer to the jet stream; the ground speed differential was 28 to 30 knots.

As the two approached California, B6 headed toward a Modesto Three Arrival (the most direct route to the 28's while United went directly overhead Mustang on the way to a circuitous Golden Gate Five Arrival. Flightaware last showed JetBlue on a final heading close to SFO while United was north of Point Reyes. The JetBlue Airbus blocked in at 2:30pm, 16 minutes ahead of the United 757. Not bad for a range starved supposedly over-matched aircraft.

Question: Was this a case of computer generated flight plan differences or something else? Was United given a lower mach number- (e.g. Mach 0.78)- to block in later because the gate would be occupied until a specific time? JetBlue had to have been flying at or around Mach 0.80 which begs the question if they are that range limited why not use LRC all the time.

What say we dispatchers and A320 drivers?

[Edited 2007-12-08 07:01:39]
 
Tristarsteve
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sat Dec 08, 2007 3:27 pm



Quoting Highflier92660 (Thread starter):
What say we dispatchers and A320 drivers?

I think you need to get out more!
 
futurecaptain
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sat Dec 08, 2007 3:54 pm



Quoting Highflier92660 (Thread starter):
JetBlue had to have been flying at or around Mach 0.80

At 38000 ft and 449 kts (speed filed from flightaware) the Jet Blue a/c would be at Mach 0.78.

At 36000 ft and 458 kts the United a/c would be at Mach 0.80.

So, Jet Blue for one reason or another, maybe gate timing, maybe traffic, maybe some other reason got the higher altitude and more favorable winds. But they were still flying a slower Mach #.
AirSO. ASpaceO. ASOnline. ASO.com ASO. ASO. ASO. ASO. ASO.
 
futurecaptain
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sat Dec 08, 2007 4:29 pm



Quoting Highflier92660 (Thread starter):

I love how your profile says "airline pilot" under occupation yet you have all these questions.
AirSO. ASpaceO. ASOnline. ASO.com ASO. ASO. ASO. ASO. ASO.
 
A342
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sat Dec 08, 2007 4:39 pm



Quoting Futurecaptain (Reply 3):
I love how your profile says "airline pilot" under occupation yet you have all these questions.

So an airline pilot is not allowed to have such questions? Maybe he flies a completely different class of aircraft and isn't familiar with the A320 and 757?
Exceptions confirm the rule.
 
musapapaya
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sat Dec 08, 2007 5:07 pm

I am interested in this as well, quite often I think about the same thing. Say on LHR-FRA, BA and LH leaves the gate together and then the LH might be in FRA 10 mins earlier, even they are using the same kind of planes. I am no pilot but I want to know a bit more.
Lufthansa Group of Airlines
 
Pihero
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sat Dec 08, 2007 6:30 pm



Quoting Highflier92660 (Thread starter):
Was this a case of computer generated flight plan differences or something else?

Very probably

Quoting Highflier92660 (Thread starter):
Was United given a lower mach number- (e.g. Mach 0.78)- to block in later because the gate would be occupied until a specific time?

I did not know UA was performing enough to plan a gate allocation / occupancy to the minute , seven hours in advance.
So IMO, unlikely

Quoting Highflier92660 (Thread starter):
JetBlue had to have been flying at or around Mach 0.80 which begs the question if they are that range limited why not use LRC all the time.

I do not have the winds aloft charts on this flight but it may well be that in the presence of a strong headwind, the LRC Mach number would be in the vicinity of .80 (depending on weight, cost index...etc...) and it seemed to have had a reasonable step cruise, therefore was close to optimum level.
Sorry, can't say more in view of the info given.

Quoting Musapapaya (Reply 5):
Say on LHR-FRA, BA and LH leaves the gate together and then the LH might be in FRA 10 mins earlier, even they are using the same kind of planes.

Now, we're talking about something quite different which is the partiality of some ATCOs for their countrymen- airlines...-.
Ten minutes would be the difference between a high speed shortened procedure to the northern runway (the one that's closest to the ramp ) and a fairly long STAR to the southern one. FRA is one of the worst practitioners of that nationalistic behaviour, though it exists in some degrees everywhere else : MXP (but not FCO ) coming close second...
'nuff said.
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highflier92660
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sat Dec 08, 2007 6:49 pm



Quoting Futurecaptain (Reply 3):
I love how your profile says "airline pilot" under occupation yet you have all these questions.

Hey I fly my Segway at 0.0082 Mach and always file IFR. My range with the new batteries is 8 mi with a 1 mile alternate diversion.
 
3201
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sat Dec 08, 2007 7:07 pm



Quoting TristarSteve (Reply 1):
I think you need to get out more!

It's OK to have these kinds of detailed discussions about maintenance topics but not operational topics like this? I see a lot of endless ramblings on some specific part, not sure why that's OK and this isn't.
7 hours aint long-haul
 
3201
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sat Dec 08, 2007 7:16 pm



Quoting Musapapaya (Reply 5):
I am interested in this as well, quite often I think about the same thing. Say on LHR-FRA, BA and LH leaves the gate together and then the LH might be in FRA 10 mins earlier, even they are using the same kind of planes. I am no pilot but I want to know a bit more.

Could be lots of things. Do you know if the filed routes were the same? Could be different procedures because of different runways expected, could be one used CDR2 for a short-cut and the other didn't. One thing it was not is flying different speeds/altitudes -- cost index 0 vs. 999 would only make 3 or 4 minutes difference.

Also you said they left the gate together and arrived at the gate 10 mins apart. In LHR they may have very different taxi times depending on their gate locations, and in FRA especially, LH never waits for a gate and other airlines do sometimes, plus if landing on 25 and LH gate is a remote stand near the cargo area or a gate at terminal A, this is a much shorter taxi than BA back to the other end of the airport; the whole difference may have been on the ground, not the air.
7 hours aint long-haul
 
3201
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sat Dec 08, 2007 7:42 pm



Quoting Highflier92660 (Thread starter):
The United aircraft never asked for higher

Never flew higher -- doesn't necessarily mean they never asked for it (although it would be unusual for traffic to keep you from 380 that far out west I guess).

Quoting Highflier92660 (Thread starter):
As the two approached California, B6 headed toward a Modesto Three Arrival (the most direct route to the 28's while United went directly overhead Mustang on the way to a circuitous Golden Gate Five Arrival.

Would be interesting to know if this flight was planned by the new system UA uses for some long-haul route planning or by their old mainframe system. I know some airlines sometimes plan into the bay area via Mustang and Point Reyes to avoid turbulence over the Sierras but I doubt UA does that. I also doubt they divert some traffic up there to avoid congestion over Modesto, that's not something operators in the US usually do.

Quoting Highflier92660 (Thread starter):
Not bad for a range starved supposedly over-matched aircraft.

The aircraft is still overmatched on that city pair, the time advantage was all about the route flown (and possibly more about the way they were operated), nothing to do with the aircraft. The A320 benefited from flying a while at 340 and flying a shorter route (and it looks like maybe a more wind-optimal one). The 757 certainly had a much higher available payload and also probably burned less fuel per lb of payload.
7 hours aint long-haul
 
highflier92660
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sat Dec 08, 2007 8:12 pm

Thanks 3201 that was a very good answer to my question. Despite the jocularity I was quite curious if it was the respective computerized flight plans or the way the two aircraft were flown. As to your last comment I'm inclined to agree; the A320 is at the edge of its performance envelope on the BOS-SFO route.
 
dispatchguy
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sat Dec 08, 2007 8:34 pm



Quoting 3201 (Reply 10):
Would be interesting to know if this flight was planned by the new system UA uses for some long-haul route planning or by their old mainframe system.

Nope, a little birdie told me that they are still using Unimatic, and that sometime in 2008 (I THINK) is when they want to turn on the new flight planning system.

Unimatic - the best of 1970s technology...  Wink
Nobody screws you better than an airline job!
 
3201
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sat Dec 08, 2007 9:26 pm



Quoting Dispatchguy (Reply 12):
Unimatic - the best of 1970s technology...

Could be worse... some people still use "not the best" of 1970s technology.  Wink
7 hours aint long-haul
 
Pihero
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sat Dec 08, 2007 11:20 pm



Quoting 3201 (Reply 10):
Never flew higher -- doesn't necessarily mean they never asked for it (although it would be unusual for traffic to keep you from 380 that far out west I guess).

 checkmark 

Quoting 3201 (Reply 10):
The A320 benefited from flying a while at 340 and flying a shorter route (and it looks like maybe a more wind-optimal one).

How do you know it flew a shorter route? And how do you know the first step at FL 340 was an advantage ? Is UAL so bad with their computers ?

Quoting 3201 (Reply 10):
The 757 certainly had a much higher available payload and also probably burned less fuel per lb of payload.

Payload, probably...Fuel burn, I'm not so sure, unless you prove it.
That's the difference between Tech-ops and civ-av.
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3201
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sun Dec 09, 2007 1:06 am



Quoting Pihero (Reply 14):
How do you know it flew a shorter route?

From the flightaware data (and as desribed by Highflier) -- flying via Pt. Reyes and GOLDN STAR is much further, especially after they were further south so crossed paths with the B6 flight.

Quoting Pihero (Reply 14):
And how do you know the first step at FL 340 was an advantage ?

By "advantage" I meant in time elapsed -- lower altitude below FL360 so faster compared to FL360 or above.... since OP asked about the A320 getting there faster. Obviously B6 did not really want to be at FL340 the whole way, and being able to go straight to FL360 is part of why the B757 probably did better in fuel burn per kg/lb of payload. Whatever you want to claim about the A320, it's not faster than the B757, and nothing about the A320 is what made it get to SFO so much sooner (except maybe for its inability to climb to FL360 initially).

Quoting Pihero (Reply 14):

Payload, probably...Fuel burn, I'm not so sure, unless you prove it.
That's the difference between Tech-ops and civ-av.

If I prove it, they will shoot me.  Smile I'll see if I can find a public source, but not likely. (Obviously only the case if the actual payload on the B757 is higher -- carrying the same payload on a larger airframe is of course less efficient.)
7 hours aint long-haul
 
LAXintl
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sun Dec 09, 2007 5:22 am

there is a LOA (letter of agreement) btwn SLC and OAK ATC center, that flts to SFO, flying at/north of SLC are to be routed to SFO via FMG-PYE. All flts south of SLC can go via MOD.
Apprtly JBU got away with one, which is not always the case.
From the desert to the sea, to all of Southern California
 
dispatchguy
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sun Dec 09, 2007 12:19 pm



Quoting Laxintl (Reply 16):
Apprtly JBU got away with one, which is not always the case.

They also couldve whined about being skosh fuel to ATC, and requested a more direct arrival into SFO than over PYE.

A319/A320s can only hold 42200 lbs of fuel on board (at least the ones I dispatched), and going west against a heavy headwind, your decision is do I fuel and leave the payload, load the payload and leave the fuel (at least anything above required reserves), or ask your duty manager if he wants to do a fuel stop somewhere and make the decisions easy.

It also depends on the engines that the JBU Busses have. At the airline I dispatched A320s, the -A1B engines on the A320 were dogs (at least when doing transcon westbounds in the winter), those -A5 engines you could carry a full transcon westbound load.

Dont even ask about an A319 with -A5s; that airplane was a pocket rocket, and had 42.2 fuel as well.
Nobody screws you better than an airline job!
 
Pihero
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sun Dec 09, 2007 1:53 pm



Quoting 3201 (Reply 15):
By "advantage" I meant in time elapsed -- lower altitude below FL360 so faster compared to FL360 or above....

In terms of TAS, flying at FL 340 iso FL 360 in normal conditions, there is a difference of only 3 kts.
Hardly a whopping advantage. Especially when you think about where the jetstream core was...

Quoting 3201 (Reply 15):
and being able to go straight to FL360 is part of why the B757 probably did better in fuel burn per kg/lb of payload.

This reasoning would also work for the 320 at FL 380 whereas the 757 kept 360.

Quoting 3201 (Reply 15):
Whatever you want to claim about the A320, it's not faster than the B757

Never said anything to that effect

Quoting 3201 (Reply 15):
and nothing about the A320 is what made it get to SFO so much sooner (except maybe for its inability to climb to FL360 initially).

So, to you, a weakness is an advantage, right ?
As a matter of fact, if you compare both tracks to the BOS-SFO great circle, the 757 was closer to it, ergo had a shorter track ; then draw a 50nm circle around SFO and verify the final track distances to the western runway. Again, hardly a big advantage.
Where the difference lies is ONLY in the generated flight plans, Jet Blue's seeming far superior in terms of optimised wind / distance / altitude / burn-off.

Quoting Dispatchguy (Reply 17):
They also could've whined about being skosh fuel to ATC, and requested a more direct arrival into SFO than over PYE.

Come on ! That's hardly normal procedure and my familiarity with US ATC tells me that the answer would have been :"are you declaring a low fuel, buddy ?" , or words to that effect. With all the consequences...

Quoting Dispatchguy (Reply 17):
It also depends on the engines that the JBU Busses have.

IAE -V2500-A5, so as you wrote :

Quoting Dispatchguy (Reply 17):
those -A5 engines you could carry a full transcon westbound load.

Quod erat demonstratum

Kind regards.
Contrail designer
 
dispatchguy
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sun Dec 09, 2007 3:10 pm

Not necessarily

The crew couldve been playing with the arrival fuel predictions in the MCDU, and asked ATC for a short cut, so as NOT to trigger a min fuel call, and all the possibly-nasty ATC pleasantries.

And yes, the A5 engines are much more powerful than the A1Bs, however, with the eastbound jet stream we had here in the states last week, even with planning a full load westbound with a comfortable fuel level for SFO (and I cant say if they needed an alternate for SFO), who is to say that the crew didnt experience a wind bust, and experience headwinds much worse than forecast, and request an ATC shortcut because of that.
Nobody screws you better than an airline job!
 
Pihero
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Mon Dec 10, 2007 1:22 am



Quoting Dispatchguy (Reply 19):
who is to say that the crew didn't experience a wind bust, and experience headwinds much worse than forecast, and request an ATC shortcut because of that.

look at the 2 min reports on that flight. The most they experienced on that flight is about 55-60 kts headwind.
As for real performance, I do not have the Jet Blue airplane specs. What I can say is that at the 77 ton option, the range for full pax load is rough;y 3000 nautical miles including a 100 Nm diversion.
On this subject, if you think that a V2500-A5 equipped 319 is a rocket, those we have here with CFM56-B7 -= an extra 3,000 lbs of thrust - are bats out of Hell !

Regards
Contrail designer
 
3201
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Mon Dec 10, 2007 8:22 am



Quoting Pihero (Reply 18):

So, to you, a weakness is an advantage, right ?

You must have missed the context and scope of the discussion.

The original poster asked whether this faster time from airport to airport was related to the aircraft, since he'd heard the A320 had trouble on the flights. I responded that the TIME was not because the A320 was faster, but that it's inability to reach a more fuel-efficient altitude initially actually did give it some time advantage.

Quoting Pihero (Reply 18):
Where the difference lies is ONLY in the generated flight plans, Jet Blue's seeming far superior in terms of optimised wind / distance / altitude / burn-off.

Because they violated (possibly with permission) the LOA. But again, that's what my response was -- that it was primarily the flight plan:

Quoting 3201 (Reply 10):
the time advantage was all about the route flown (and possibly more about the way they were operated), nothing to do with the aircraft.

Great circles are irrelevant with winds, but the arrival via MOD is shorter than going around the outside via PYE and the GOLDN STAR.

The OP asked whether the A320 had some advantage, I answered that it did not, that the 757 is faster but the A320 had a shorter planned route that day. I really don't know what your issue is, it almost sounds like you're trying to "defend" the A320, which I'd expect more in Civ Av than in Tech Ops. All my responses were objective analysis to help the OP with his question.
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HAWK21M
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Mon Dec 10, 2007 8:42 am



Quoting Futurecaptain (Reply 3):

Quoting Highflier92660 (Thread starter):


I love how your profile says "airline pilot" under occupation yet you have all these questions.

Whats wrong in case a Qualified Pilot asks a related question.If there were no questions, there would be no debate & no forum.
He may be qualified on a different type & is keen on knowing more.

regds
MEL
I may not win often, but I damn well never lose!!! ;)
 
Pihero
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Mon Dec 10, 2007 10:24 am

Dear 3201

Quoting 3201 (Reply 21):
I responded that the TIME was not because the A320 was faster, but that it's inability to reach a more fuel-efficient altitude initially actually did give it some time advantage.

So, where did I misquote you ? A weakness is a disadvantage...

Quoting 3201 (Reply 21):
Because they violated (possibly with permission) the LOA. But again, that's what my response was -- that it was primarily the flight plan:

Again, what proof do you have on that *violation* ? Have you got the initial flight plan in hand ?

Quoting 3201 (Reply 21):
Great circles are irrelevant with winds,

Yes, but the UA flight had a shorter ground track, which seems to prove that they planned closer to the 'jet core than JB.

Quoting 3201 (Reply 21):
I answered that it did not, that the 757 is faster but the A320 had a shorter planned route that day.

See above. They planned smarter.
And nothing would prevent them to design a far northern route than the jet and then "plunge" schuss over SLC and take advantage of the Modesto arrival.

Quoting Highflier92660 (Thread starter):
As they flew over southern Idaho B6 at FL380 was clearly ahead with the United 757 slightly south and closer to the jet stream; the ground speed differential was 28 to 30 knots

There is your proof of the better planning : Those 30 kts translate into -assuming the 320 was at M .78 and the 757 at M .80 - differential headwind component of some 42 kts ...--> the 757 was giving away some 4 minutes per hour to the 320, at the time when the 320 was higher. So your argument of a shorter route falls to pieces.

Quoting 3201 (Reply 21):
I really don't know what your issue is, it almost sounds like you're trying to "defend" the A320, which I'd expect more in Civ Av than in Tech Ops. All my responses were objective analysis to help the OP with his question.

Objectivity comes with facts and proof. Your responses were all about 757 superiority and 320 violations...with very little to back you on this subject.
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3201
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Wed Dec 12, 2007 6:24 am

Pihero, I still don't understand what you're talking about. My very first comment about the difference was:

Quoting 3201 (Reply 10):
the time advantage was all about the route flown (and possibly more about the way they were operated), nothing to do with the aircraft.

I said it was the route planned that was the advantage. You keep trying to tell me that I don't understand that B6's route was better.

Apparently your argument with me is because I said the B6 route was shorter. While the enroute portion was longer, taking the short-cut they did from where they crossed paths with the UA route was indeed shorter. IComparing OAL.MOD3 with PYE.GOLDN5 from any point NE of FMG, OAL.MOD3 saves about 5 minutes and the corresponding amount of fuel. Yes, B6 had a better route earlier which was legit, but they gained a lot from flying a shorter ground track in the end as well (not air distance, ground distance). I have the winds from that day, and flying the B6 route but via PYE.GOLDN5 is still better than UA's route but not as much better.

The OP clearly asked this question because he was surprised the A320 could beat the 757. I told him it was not the aircraft, it was about the route, and that a 757 is faster. Are you really disputing that?
7 hours aint long-haul
 
Pihero
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Wed Dec 12, 2007 9:00 am



Quoting 3201 (Reply 24):
Yes, B6 had a better route earlier which was legit, but they gained a lot from flying a shorter ground track in the end as well (not air distance, ground distance).

That's one of my gripes with you : The 320 had a longer ground track, being farther north of the great circle and the *kink* south to the MOD arrival.

Quoting 3201 (Reply 24):
I have the winds from that day, and flying the B6 route but via PYE.GOLDN5 is still better than UA's route

Give us the url, then, instead of affirmations.

Quoting 3201 (Reply 24):
Pihero, I still don't understand what you're talking about.

I will agree that your first proposition ( advantage due to route flown ) was essentially correct, but when you declare that it was only possible through *illegal* flight management I can't accept your assertion.
In terms of operations, the *kink* I mentioned, when backed-up by the details of the flightaware details prove that they were flying at a much higher ground speed than on the west-oriented track, because much of the strong wind was then reduced to a cross-wind. When they resumed their westbound course to Oakland, they descended under the jet.
Brilliant planning.

Quoting 3201 (Reply 24):
a 757 is faster. Are you really disputing that?

You seem to be the one trying to defend an aircraft at all costs to the point of rubbishing an airline flying the competition, are you not ?

Regards.
Contrail designer
 
rsbj
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Thu Dec 13, 2007 2:43 am

I am surprised no one has mentioned this yet, but it is entirely possible that the United pilots intentionally flew lower and or slower in an effort to show management their displeasure, or to make more $ as they are paid by the hour. That happened a lot at my previous airline.
I fly really fast and take a lot of chances.
 
Pihero
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Thu Dec 13, 2007 1:40 pm

Quite unprofessional if it was the case...
In fact, unacceptable.
Contrail designer
 
3201
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sat Dec 15, 2007 8:16 am



Quoting Pihero (Reply 25):
I will agree that your first proposition ( advantage due to route flown ) was essentially correct, but when you declare that it was only possible through *illegal* flight management I can't accept your assertion.

Laxintl pointed out that there was an LOA between Salt Lake and Oakland centers, and I looked into it and found that was correct. The B6 route violated that LOA. I'm not aware of a public place where the LOA's are published.

Quoting Pihero (Reply 25):

Give us the url, then, instead of affirmations.

Sorry, I don't have them on a public website. If you can find them archived anywhere publicly available, I'll help you with the calculation.  Wink
7 hours aint long-haul
 
timz
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sat Dec 15, 2007 10:44 pm



Quoting Laxintl (Reply 16):
there is a LOA (letter of agreement) btwn SLC and OAK ATC center, that flts to SFO, flying at/north of SLC are to be routed to SFO via FMG-PYE.

Going thru the flightaware flight plans, it says DL 411 JFK-SFO for 14 Dec was flightplanned

COATE J36 FNT GRR ODI J34 RWF HON RAP ECS BOY MLD J158 MVA MOD3

Gotta check the chart, but offhand I'm guessing that's contrary to the letter?
 
Pihero
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sat Dec 15, 2007 11:56 pm



Quoting Timz (Reply 29):
Gotta check the chart, but offhand I'm guessing that's contrary to the letter?

Thank you,Timz, it does seem contrary to the assertions of previous posters.
Can someone provide us with the text of that LOA, please ?

Quoting 3201 (Reply 28):
The B6 route violated that LOA.

I really think a change of vocabulary is in order, here.

Regards
Contrail designer
 
3201
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Fri Dec 21, 2007 1:16 am

Quoting Pihero (Reply 30):
I really think a change of vocabulary is in order, here.

Why? What word do you object to?

I'm trying to figure out what I ever did to make you decide you can't stop until you can find something I've said that's wrong.

[Edited 2007-12-20 17:48:30]
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Pihero
Posts: 4196
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Fri Dec 21, 2007 7:54 am



Quoting 3201 (Reply 31):
Why? What word do you object to?

See the meaning of *violation* in this context, for instance.
Contrail designer
 
3201
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sun Dec 23, 2007 2:37 am



Quoting Pihero (Reply 32):
See the meaning of *violation* in this context, for instance.

From the information I have, that route violates the agreement in the letter. Not sure what your objection is. For instance? Do you have more examples?
7 hours aint long-haul
 
LAXintl
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Sun Dec 23, 2007 5:07 pm

FDC 6/7901 (A4557/06) - SPECIAL NOTICE
ON AUGUST 3, 2006 0608031200 UTC OAKLAND CENTER REDEFINED
AIRSPACE SECTOR BOUNDARIES TO INCREASE CAPACITY AND REDUCE
TRAFFIC COMPLEXITY. RNAV AIRCRAFT DEPARTING SFO, OAK, AND SJC
NORMALLY ROUTED OVER LIN.J84 SHOULD FILE ONE OF TWO NEW DIVERGING
ROUTES: LIN..PEONS..INSLO..DTA OR LIN..JSICA..ILC. AIRCRAFT
ARRIVING SFO VIA THE VICINITY OF MLD, OCS, TCH, OR LCU SHOULD FILE
OVER FMG..ILA..PYE.GOLDN4. AIRCRAFT ARRIVING SFO VIA MTU, DTA, OR
ILC SHOULD FILE OVER RUMPS..OAL.MOD3. AIRCRAFT ARRIVING OAK IN THE
VICINITY OF MLD, OCS, TCH, OR LCU SHOULD FILE OVER FMG.RAIDR2.
AIRCRAFT ARRIVING OAK VIA MTU, DTA, OR ILC SHOULD FILE OVER
TATOO..DUGLE.MADN4. AIRCRAFT ARRIVING SJC FROM THE NORTHEAST SHOULD
FILE FMG.HYP5. AIRCRAFT ARRIVING SJC FROM THE EAST SHOULD FILE
TPH..CANDA.HYP5. THIS INFORMATION HAS ALSO BEEN DISSEMINATED VIA AN
IMPACT STATEMENT THROUGH THE ATCSCC. PLEASE REFER ANY QUESTIONS
REGARDING THESE PROCEDURES TO JAMES SPILLANE /ZOA/ 510-745-3615. WIE UNTIL UFN.
CREATED: 07 DEC 20:51 2006
From the desert to the sea, to all of Southern California
 
PHLapproach
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Mon Dec 24, 2007 4:04 am



Quoting Pihero (Reply 30):
Quoting Timz (Reply 29):
Gotta check the chart, but offhand I'm guessing that's contrary to the letter?

Thank you,Timz, it does seem contrary to the assertions of previous posters.
Can someone provide us with the text of that LOA, please ?

Very late on this, but here you go. Nothing in the LOA about special routing instructions for SFO Landers. But here is SJC and OAK. If there was a restriction, it would be right next to one of these.

(12) All San Jose (SJC) arrivals will be routed over Mustang (FMG) or Coaldale (OAL)
for the appropriate STAR and transition.
(13) All Oakland (OAK) arrivals will be routed over FMG, Mina (MVA) or OAL for the
appropriate STAR and transition. Arrivals that are south of J84 may be routed over
DUGLE intersection and then via the appropriate STAR and transition.
 
LAXintl
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RE: A320 Vs. 752/ BOS-SFO Flight Plan Differential

Mon Dec 24, 2007 7:42 am

what about the FDC NOTAM 6/7901 ?
AIRCRAFT ARRIVING SFO VIA THE VICINITY OF MLD, OCS, TCH, OR LCU SHOULD FILE
OVER FMG..ILA..PYE.GOLDN4. AIRCRAFT ARRIVING SFO VIA MTU, DTA, OR
ILC SHOULD FILE OVER RUMPS..OAL.MOD3.
From the desert to the sea, to all of Southern California

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