Why the 757 on EGLL - KJFK?

[CAY165 - Liam]

Its simply the fact that the 757 cant make the route even with full fuel if you fly the proper route and not direct gps and even doubt it would make it then. Jon could you please review this problem thumbup

[CAY017-Aharon]

Shalom Liam,

If many airlines in real life can fly from KJFK to Heathrow via 757s, I am sure you can too:):):)

What version of 757 are you using? POKSY or Captain Sim?

When I use economical speed (0.78 mach) for POSKY 757s, I average 20 percent of fuel consumption per 1,000 nautical mile so the plane can go 4,500 nautical miles non stop.

Try loading 85 percent of fuel on your POKSY 757 and fly at mach 0.80 from KJFK to Heathrow. When you depart from KJFK, request to ATC for LONGEST runway they have.

Regards,

Aharon

[CAY165 - Liam]

ooo wat airlines use the 757 for transalantic flights? Im preety sure from what i could see that even if i consurved my fuel and flew "econimically" i still would not have made it.

[CAY102- Jon]

Alot of companies are flying the 752 accros the pond. In fact, if airlines saw the frames potential a little sooner, I'm sure Boeing would still be making them. It seems tailor made for transatlantic, thin routes (DL and US both fly the 752 to BRU, as does CO every once and a while and did NW when they shortly returned to BRU).

Continentel actually was the first to introduce the 752 on a large scale to Europe, followed by other airlines. This way they can serve smaller markets (or well served markets like BRU-NYC) as efficient as possible.

Now, being a narrowbody isn't actually harming the 752. It seems more cramped then a widebody, but it's not that big an issue, it's mostly the double aisle that creates a spacious feeling in widebodies, as far as seat room matters, the difference is not that big. CO even has AVOD in their 752 and not (yet) in their 76X fleet.

[CAY165 - Liam]

ok good thanks for the answer but that still does explain while i was fully fueled and by half way about 2 thirds of my fuel was being used. i really think we should just use the 777 for our translantic flights.

[CAY017-Aharon]

Now, being a narrowbody isn't actually harming the 752. It seems more cramped then a widebody

Shalom Jon,

I agree with you that many 757s have very cramped seatings. However, Delta's newly renovated 757-200s and 757-200Ws have more roomy seating arrangements. Delta is in middle of renovating all 757s' seating arrangements to make seatings more roomy and less cramped.

I once flew from Salt Lake City to NYC on Delta 757 (see pics of snowy airport on other forum) and the seating arrangement was as ROOMY as JetBlue's.

Unfortunately, few days ago, I flew on a 757 and the seating was so cramped that stewardesses could notice that I had hard time sitting with very long legs so they moved me to front row!!! I am tall person!!

Regards,

Aharon

[CAY017-Aharon]

ooo what airlines use the 757 for transalantic flights? Im preety sure from what i could see that even if i consurved my fuel and flew "econimically" i still would not have made it.

Shalom Liam,

Did you know that NorthWest (NW) flies 757s non stop between Detroit and Germany???

Liam, what altitude do you usually fly your 757? Maybe you fly at wrong altitude that can result into higher fuel consumption?? How do you take off and climb? Taking off and climbing in POKSY 757 should consume 5 percent of fuel.

Also, unrealistic weather settings can eat up too much fuel.

I tested POSKY 757 many months ago by flying from KJFK to Heathrow at 0.78 mach economical speed taking off with 100 percent fuel (do not attempt this as NO airlines would take off with 100 percent fuel and I was testing the plane's fuel consumption rate) and I arrived at Heathrow with 40 percent remaining fuel.

Regards,

Aharon

[CAY165 - Liam]

did you fly using the latest NATS and fly the real world route?

[CAY792-William]

The 757 with its new ETOPS regulations are able to fly all NAT rotues. The airlines that are flying the 757s across the Atlantic have to have a certian records and have to fly the aircraft for a number of years before they are granted the lowest ETOPS that there is (120). After many more years, they can apply for longer range ETOPS which is why now the B757 can fly across the pond on the NAT routes.

The B757 tho has been used from the west coast to Hawaii which is around the same distance as London-New York for a couple of years also and in actual fact its worse off than crossing the atlantic! They dont have any alternates along the way that thay can divert to so they really have to hope they dont have problems!

the B757 has a total range (non-restricted) 3,900nm, or with winglets 4,100nm! They have plenty of gas in them to cover the atlantic.
However sometimes when the winds are very strong across the atlantic and they NATS cant find a quiet wind route, they due make the odd tech stop in either Shannon, or at Gander to just pick up a little gas.


Also a little side note:
BA plan to launch A318VIP services from London City to New York this year.
The A318 will however need to make a fuel stop at Shannon in Ireland. However as Shannon has US Immigration, the passengers can clear US Immigration and Customs there and then takeoff to New York and as soon as they land, they can head out the terminal.
The flight back from New York is nonstop as the winds will be helping the aircraft so they dont need to stop in Shannon going that way.

[CAY505- Tim]

B757's have been ETOPS 180 mins since at least the early to mid 1990's. I was dispatching B757's around the world in 1994 crossing the North Atlantic, North Pacific, as well the smaller Oceans such as the Indian and Arctic. Chance are that if you are using real world weather you caught some nasty headwinds going westbound. The NATS are built twice a day to match up with the primary Eastbound and Westbound Euro-US traffic and normally are built base upon the prevailing winds. Near the jet normally Eastbound to capture extra tailwind, away from the jet Westbound to avoid the nasty headwinds. Some days, it does not matter what you do, you are not going to avoid strong headwinds and those days usually occur in the winter when the lower altitude winter jet in the Northern Hemisphere becomes the dominant jet at the mid latitudes.

Most airlines that are crossing oceans are using flight planning systems that are designed to build the best wind routes for a given city pair at a given time. It will alter course, altitude, and speed to match whatever parameters the airline and/or dispatcher desires. These flight planning systems will hook into the the NAT Tracks for the oceanic portion of the flight and then maximize the wind route getting to the NATS and exiting the NATS.

Chances are, you will not find a flight planning system that will do that for you in FS. The NATS get published twice daily (Once Eastbound and Once Westbound) and are probably available on line which should provide some idea where the most efficient routes are over the ocean. The center most route is normally the most efficient, but not always. There are 10 Degrees of latitude between each track (aprox 60 NM) so the efficiency does vary from track to track.

As much as it seems counter intuitive, sometimes the direct line between two airports is not the fastest route. I have seen a flight plan for a B757 from the Azores to KPHL that set the route of flight almost due north for 150 NM before turning westbound and onto the Northeast US. The route ended up being almost 175NM longer than the most direct route but 45 minutes faster due to the wind patterns. I have dispatched a B777 from KSFO to KMIA that went due south to KLAX before turning east that was 30 minutes faster by catching a tailwind over the Southern US rather than taking the more direct route Eastbound out of SFO. Its a concept that most air traffic controllers and even some airline pilots do not understand until you draw them a picture.

[CAY017-Aharon]

I have dispatched a B777 from KSFO to KMIA that went due south to KLAX before turning east that was 30 minutes faster by catching a tailwind over the Southern US rather than taking the more direct route Eastbound out of SFO.

Tim,

What airline flies 777 from KFSO to KMIA??

Regards,

Aharon

[CAY505- Tim]

Tim,

What airline flies 777 from KFSO to KMIA??

Regards,

Aharon

UAL used to. I used to have B777's coming off KSFO and KLAX for KMIA every afternoon my desk. Sometimes they would go down to a B767-300 in the off peak times of year, but it was a big South Amercian feed for UAL at the time. Both flight numbers would continue from KMIA down to South American cities ( Sao Paulo, SBSP and Rio de Janeiro, SBGL if I recall correctly) and provided feed from the West Coast of the US and international connections from the Pacific Rim cities arrivng in KSFO.

[CAY017-Aharon]

UAL used to. I used to have B777's coming off KSFO and KLAX for KMIA every afternoon my desk.

Tim,

Thanks for reply. Speaking of your desk, what do you do for living in aviation, please? Are you airport controller??? You said that controllers and pilots sometimes do not understand and do not have clue about fuel management in conjunction with weather winds. I am guessing you must have been occupying some important airport position that is better than controllers????

Regards,

Aharon

[CAY102- Jon]

He's a bell hop rollseyes :lol:

Occupations can typically be found in member's profiles :))

[CAY505- Tim]

Tim,

Thanks for reply. Speaking of your desk, what do you do for living in aviation, please? Are you airport controller??? You said that controllers and pilots sometimes do not understand and do not have clue about fuel management in conjunction with weather winds. I am guessing you must have been occupying some important airport position that is better than controllers????

Regards,

Aharon


Just a lowly dispatcher, no better than a pilot or an ATC controller, some would argue its a worse place to be.

The reference to pilots and controllers not fully understanding how the wind patterns work is from several years of dealing directly with both. The Controller and Pilot mentality has tradionally been "direct is the fastest route". While the majority of the time it may well be the fastest and most efficient route, it is not always the case. Upper air winds are not consistant in direction and speed for an entire route of flight and can even vary based on altitude for a given route of flight. Altering the route to take advantage of increased tailwaind components or avoiding increased headwind components can provide significant fuel and time savings. The longer the flight, the more time and fuel you can save by flight planning to take advantage of the wind patterns. The reason most folks miss these opportunities is that there are not really any usable tools for controllers and pilots to use to see the difference between the best wind route and the most direct route. Since dispatchers are constantly planning flights and have access to dynamic flight planners that can take advantage of a given wind pattern, we tend to see the advantages a bit more clearly (of course, there are a lot of dispatchers that don't understand the concept either).

Even before higher tech flight planning systems came along, you could still get some benefits of "pressure pattern" flying on longer range flights by altering the route of flight on the "tailwind side" of a high or low pressure region. With modern flight planning systems, we can obtain an amazing amount of effeciency flying based on wind patterns. Getting over the hurdle of "direct is always fastest" can be quite difficult at times, but once folks start to understand the benefits they quickly convert. I used to have some progressive Captains who contact me any time they received a "short cut" offer from ATC to see if it truely would save time/fuel over the originally filed route they were flying. After running it through the system, we could then make an educated decision on whether to accept a shorter distance route or stay on the wind effecient route.

Modern FMC's have ability to analyze an alternate routing, but it requires the crew to manually enter in the wind data for every fix down line in order for it to be accurate. Additionally, it can only compare it to the currently entered route in the system. It is faster for the crew to send the proposed routing to their dispatcher and have them analyze it with the current wind data already in the database and run the route through the flight planning system for time/fuel comparisons. Another down side to FMC's is the previously mentioned wind data. Unless the downline wind data has been ingested with the FP or manually entered into the FMC, the FMC assumes that whatever the current wind is where it is currently located will be the wind for the remainder of the flight. Wind speeds will vary quite a bit from point to point so the fuel numbers in the FMC can be a bit exaggerated (to the good or bad) if the flight is in a low wind speed or high wind speed area as the FMC extrapolates that wind over the course of the rest of the flight plan.

ATC controllers have even less information when it comes to winds. There systems are primarily designed to keep aircraft seperated and to manage flows into and out of airports. They have weather data, but not taylored to enroute winds. With the advent of modern flight planning systems, ARTCC's have become more savy on the enroute winds as airlines end up flight planning their flights along similar routings to take advantage of the wind patterns. All that traffic will overload sectors if they do not manage it, so it has been a necessity for them to learn more about it.

Tower and TRACON controllers will look at you stange if you tell them direct is not always the fastest route. I have sat in a room with 20 or so controllers having an argument over this very subject. Its not their fault, they just do not have to deal with it on a daily basis and if they have not been in an enroute facility they probably have never even been trained on it. Once you draw a picture on the board or a piece of paper with wind patterns and a route of flight, they understand almost immediately.

Its not a tough concept, but if everything you have ever done has always lead to direct is faster, why would you think anything different? Its kind of like jumping into water. If someone told you that you could jump into a body of water and stay completely dry, you would not believe them and have them prove it to you. No?

[CAY505- Tim]

He's a bell hop rollseyes :lol:

Occupations can typically be found in member's profiles :))

Bell Hops get better tips that I do.:lol:

[CAY017-Aharon]

Thanks Tim and Jon for replies

Thanks Tim for extensive well written explanations.

Would appreciate double spaced explanations in future as it is hard to read long explanations in single spaced paragraphs on computer screen:):)

And nice to meet you on the forums, Tim. Do not worry I would not nickname you the bellhop.

When you said captains call you to verify ATC controllers' suggestions for shortcuts, do you mean the captains walk to your desk and talk to you OR the captains call you from their planes' cockpits via radios??

Regards,

Aharon

[CAY792-William]

Normally If ATC give a better routing, the Captain would call up UAL Dispatch on their company radio. It will be a frequency that the pilots can tune into to talk to their dispatch.
As for ATC giving you a "better" route, I would say that it would normally be a short-cut on the route that the aircraft is flying. It is highly unlikely that ATC are gonna request that an aircraft take a completely different route from the one the pilot has planned as it first of all takes up time and also when you are trying to watch 20 other aircraft, you cant stop and help out one aircraft understand his new routing!
The only time i could see this is from traffic congestion and im gonna say that 99% of the time the pilot will take the short-cut as if it means he gets up faster to his cruise level, then he doesnt have to sit down at lower altitudes and burn more fuel.

In reference tho to the dispatch side Aharon, pilots normally show up way in advance of their flight to get all the details from the dispatch crew who have normally done all the pilots work!
They basically do all the hard stuff so that the pilot just has to check it all out and then sign off on it!

Dispatch involves:
Getting the best route for the flight based on the weather and list a couple of alternates incase the aircraft needs to divert
Print out all Notams for the pilot on all the appropriate airports that the aircraft is flying to (including the alternate airports)
Calculate the amount of Fuel needed from the wind data, loads on the flight and then also calculate the fuel burn they estimate to have.
Give the captain his weight and also where the Center of Gravity is going to be on the flight.

The captain has to look over all of this and if he wants to change anything then he will go back to dispatch and convey with them what he feels about the changes and then they go back and calculate it all over again for him. He then signs off on it and then he heads out to his aircraft for the flight.

I actually saw a film on a UAL 772 from ORD-LHR-ORD and that baby has some great features it uses to allow the captain to get all the details from his dispatch via a Datalink!
He showed us that he didnt have to enter the whole flight plan into the FMC! All he did was send a request from it to dispatch and then it came back into the FMC with it all done!
Also he showed us the Datalink which allowed him to send details all throughout the flight about the kind of ride he was experiencing all the way across the atlantic and the wind data so that dispatch can then either send their other aircraft along it or avoid it all together!
The pilot even requested his NAT Track clearance via this datalink to the ATC in Canada which was very cool!
These pilots no a days do nothing it seems!!

[CAY505- Tim]

Normally If ATC give a better routing, the Captain would call up UAL Dispatch on their company radio. It will be a frequency that the pilots can tune into to talk to their dispatch.
As for ATC giving you a "better" route, I would say that it would normally be a short-cut on the route that the aircraft is flying. It is highly unlikely that ATC are gonna request that an aircraft take a completely different route from the one the pilot has planned as it first of all takes up time and also when you are trying to watch 20 other aircraft, you cant stop and help out one aircraft understand his new routing!
The only time i could see this is from traffic congestion and im gonna say that 99% of the time the pilot will take the short-cut as if it means he gets up faster to his cruise level, then he doesnt have to sit down at lower altitudes and burn more fuel.

Re-routes normally occur either on the ground or after the flight has reached cruise altitude. Inside the terminal areas, most route changes are highly dynamic and are usually not requests from ATC but rather instructions to keep traffic flows seperated and to fit the aircraft into the arrival or departure streams. Routes into and out of major terminal areas are fairly rigid in the real world and shortcuts are normally not offered until you are beyond 200NM from the terminal area.

Enroute re-routes are fairly common on longer haul flights, and ATC will offer flight more "direct" routings if there are not volume/weather constraints at the crew's request. If a crew hears a flight ahead of them on frequency get a direct, chances are the following crew will ask for the same thing. The smart ones will contact dispatch prior to doing so to see if the direct routing will in fact be beneficial. At UAL, we had the ability to datalink the revised flight plan right into the FMC so that the latest wind data was available to the crew with the updated flight plan, but not all airlines use that capability as there is a cost associated with sending all that data via VHF radio signals or Satellite signals.

Normally, a crew will contact dispatch via the ACARS system which is a datalink system using either VHF radio waves or Satellite signals when outside of their ACARS providers VHF network. For airlines without ACARS capability or if the crew so chooses, you can contact dispatch via a VHF radio network that connects into the phone system for what is normally termed a "phone patch". If the aircraft is within VHF range of the dispatch facility, there are also air to ground radios that can be used to communicate. When outside of VHF radio range, you can use HF radio or a more modern Satellite communication system (which is significantly more expensive to operate). If you want to simulate an HF phone patch, take an old analog cell phone and place it inches next to a pan of frying bacon and then try to communicate with someone on the other end of the line. If your lucky, you will not get the echo (hearing what you yourself said 3 seconds ago as your still talking) which made giving coordinates of a re-dispatch fix to a flight over the ocean a ton of fun. SatCom was like talking to someone right next to you in a quiet room.



Captain's walking up to a dispatch desk in the States is something that is from a bygone era. Some small airlines and cargo airlines may still have that opportunity, but for the most part it is done over the phone, via radio, or via data link from the cockpit. In my first dispatch job, we would occasional get a crew picking up a plane at the hanger come up to the office to pick up their paperwork, but normally they will pick it up in the operations office of the airport. Sadly, I know more Captains by name and voice alone. I could not pick them out of a line up if you paid me.

[CAY017-Aharon]

Thanks Williams and Tim for interesting explanations!!!

I would appreciate that in future if anyone wants to present very long explanations, he or she should type double space, not single space please as it is giving me dizzy to read long single spaced explanations on my laptop screen.

Smiling

or you can increase font if you do not want to use double space

Regards,

Aharon