Comparing the 757-200 and the 737 Max10

[Tim Jodice]

I was flying airlines last week and seeing the size difference of a 737 and a 757 up close had me wondering why.

Both seat up to about 200 people and six abreast narrow body seems to be all that they have in common.

I know the name of the game is fuel efficiency but wasn't it important in the late 70s when the 757 was designed? I can't imagine the fuel crunch of 73 had been forgotten.

They felt it took a aircraft as substantial as a 757 to carry about 200 people about 3000 miles. And today they do it with a heavily modified 737. 

Some numbers,

The 737-10 

Gross weight is about 200,000, 4 main gear wheels, the most powerful leap engine has about 35,000 pounds of thrust.

The 757-200

Gross weight is about 255,000, 8 main gear wheels, the engines have about 43,000 pounds of thrust.  

The part that seems strange to me is the fact the 757 was designed in the late 70s (first flight 1982) from the ground up to carry 200+ people. I couldn't find anything about them getting updated for efficiency. Yet they take an airplane that was designed in the early 60s (first flight 1967) for a different mission and heavily modifying it. 

I am sure a 737-10 is way more efficient than a 757-200. The most obvious reason is one of the engines used in the 757 is the Rolls Royce RB211 first run in 1967. The 737 gets the GE LEAP B1 first run 2014.

I am no engineer but I am sure they learned a thing or two about efficiency in 47 years.

If money was invested in upfating the 757 for efficiency would it still be so inefficient?

The mechanic that I am sees this like taking a Freightliner FL80 and using it as is or getting a Ford F350 and heavily modifying it. Then your hopefull it works.

What is every one's thoughts?

 

[jetdriven]

757burns over 7000 pounds an hour, while the 737 max 10 is going to burn around 5000. 

But the 757 has tremendously better runway numbers, and it’s got a lot more range. They may be able to fly the max 10 to Shannon Ireland from EWR  on the best of days, but the 757 goes to anywhere in Europe. 3300 miles of range versus 4500.  So will the A321 neo XLR. 
So here is where Boeing went sideways, the 757 was obsolete, the 737 could not really be stretched any further. They did not have a Viable long range  narrowbody midmarket airplane. Instead of spending 35B on a new plane, they bought 45B in stock back   

 

[Captnmack]

25 minutes ago, airtim said:

I was flying airlines last week and seeing the size difference of a 737 and a 757 up close had me wondering why.

Both seat up to about 200 people and six abreast narrow body seems to be all that they have in common.

I know the name of the game is fuel efficiency but wasn't it important in the late 70s when the 757 was designed? I can't imagine the fuel crunch of 73 had been forgotten.

They felt it took a aircraft as substantial as a 757 to carry about 200 people about 3000 miles. And today they do it with a heavily modified 737. 

Some numbers,

The 737-10 

Gross weight is about 200,000, 4 main gear wheels, the most powerful leap engine has about 35,000 pounds of thrust.

The 757-200

Gross weight is about 255,000, 8 main gear wheels, the engines have about 43,000 pounds of thrust.  

The part that seems strange to me is the fact the 757 was designed in the late 70s (first flight 1982) from the ground up to carry 200+ people. I couldn't find anything about them getting updated for efficiency. Yet they take an airplane that was designed in the early 60s (first flight 1967) for a different mission and heavily modifying it. 

I am sure a 737-10 is way more efficient than a 757-200. The most obvious reason is one of the engines used in the 757 is the Rolls Royce RB211 first run in 1967. The 737 gets the GE LEAP B1 first run 2014.

I am no engineer but I am sure they learned a thing or two about efficiency in 47 years.

If money was invested in upfating the 757 for efficiency would it still be so inefficient?

The mechanic that I am sees this like taking a Freightliner FL80 and using it as is or getting a Ford F350 and heavily modifying it. Then your hopefull it works.

What is every one's thoughts?

 

There is NO comparison. The 757 is far more capable, superior and comfortable. Even in a center seat!

[Tim Jodice]

12 minutes ago, jetdriven said:

the 757 was obsolete   

In its original design. Was it a bad platform for updating? 

[jetdriven]

Im not sure why it wasn’t updated. It shares the same tube as the 737 but it’s longer, wider, taller, heavier airplane.  Perhaps there aren’t many candidates for more efficient engines in the 45k thrust class. 

[M20F]

2 hours ago, Captnmack said:

There is NO comparison. The 757 is far more capable, superior and comfortable. Even in a center seat!

True but the fiscal components do not support the 757, which is why they are gone.  I really liked L-1011’s as well but again the math just doesn’t work. 

[Captnmack]

Well look how much the bifurcated Max has cost! A new engine and wing clean up and NG glass and FMS...

[M20F]

2 minutes ago, Captnmack said:

Well look how much the bifurcated Max has cost! A new engine and wing clean up and NG glass and FMS...

More then Boeing would like, less then the strategy you imply. 

[Captnmack]

BTW, from the thumbnail I like your F...That’s my goal with mine...

[flyboy0681]

3 hours ago, airtim said:

I was flying airlines last week and seeing the size difference of a 737 and a 757 up close had me wondering why.

Both seat up to about 200 people and six abreast narrow body seems to be all that they have in common.

I know the name of the game is fuel efficiency but wasn't it important in the late 70s when the 757 was designed? I can't imagine the fuel crunch of 73 had been forgotten.

I have actually thought about this very subject a lot, and then some. This really came to a head with me when I opened the December issues of Flying, where an article appeared on how the 757 may just have been the best airliner of all time and how Boeing got everything right about it. I know it's all about cost per seat mile and wondered why a new engine couldn't have been developed or an existing one made more efficient for the 757 platform since current and future Airbus and Boeing products could more than likely make use of it. I've always enjoyed riding on the 757, mostly because of how it earned it's nickname as the "hot rod" and how it appeared to be more quiet in the cabin than all of the 737 variants.

But I think one of the most striking things about the current crop of 737 is how it has reached the same size as the 707 in terms of passenger capacity. I can't help but think that had the same engine technology been available when the 707 was designed, it would look identical to a 737 - a low to the ground, twin engine aircraft. Let's face it, the age of three and four engines attached to a passenger jet are long gone. Just sit and watch arrivals at a busy airport and you'll notice that 90% of all aircraft have two engines. Compare that to peering out the same window in 1985.

https://webcache.googleusercontent.com/search?q=cache:zp7FMl99ISYJ:https://www.flyingmag.com/story/aircraft/boeing-757-a-modern-classic/+&cd=1&hl=en&ct=clnk&gl=us

[bradp]

I used to be pax on 752s out of SNA “rocketship departure” quite often.  What the 75s did, they did extremely well. 

[Davidv]

Ah the age old discussion of avgeeks everywhere (including me), wishing Boeing continued to produce the 757...

I’m sure many on this forum have flown the 757 for work but I was speaking with my retired AA pilot cousin who said that was his favorite to fly.  He recalled one time when he was ferrying one with just the crew and did a 6k fpm climb To 6k feet...

Edited January 21, 2020 by Davidv

[BDPetersen]

Delight to fly, outstanding performance. Well, maybe the B720 could outclimb. For some of us it was the first glass cockpit, fms experience. (“Why the hell did it do that?”). Rejiggering our discipline to a two pilot cockpit was an issue. Favorite? Certainly. Sentiment favorite? B727 probably.

[PT20J]

Peter Morton headed the team at Boeing that designed the 75/76 flight decks. He once told me that the biggest problem in early service was that everything was so automated (in order to eliminate the FE) that there was little to do in cruise and the pilots would get into discussions about what they had learned in ground school and try stuff. “Let’s what happens when we flip this switch...”

I think the 727 was Hoot Gibson’s favorite, too.

Skip

[jetdriven]

Interestingly the 737 has no EICAS system. Like the 1978-designed 757 that is out of production. 

[flyboy0681]

2 minutes ago, jetdriven said:

Interestingly the 737 has no EICAS system. Like the 1978-designed 757 that is out of production. 

Considering that the personal computer hadn't even been invented yet, that was very high-tech for the time and the display was relatively high resolution, even by today's standards. Somebody was definitely thinking outside the box at the time.

[Oscar Avalle]

On 1/20/2020 at 8:25 PM, Davidv said:

Ah the age old discussion of avgeeks everywhere (including me), wishing Boeing continued to produce the 757...

I’m sure many on this forum have flown the 757 for work but I was speaking with my retired AA pilot cousin who said that was his favorite to fly.  He recalled one time when he was ferrying one with just the crew and did a 6k fpm climb To 6k feet...

When I was posted to La Paz, Bolivia, the only plane that was able to fly Miami - La Paz (the airport is at 14,000 feet) was the 757. Even at that altitude take off performance was nice, while the 737 or the 320 that other airlines used felt anemic to say the least. 

[LANCECASPER]

Someone that should weigh in on this is @StevenL757

[GeeBee]

I will chime in here with some experience. I have thousands of hours in both. I was a Check Airman on both.

The main reason why Boeing ended the 757 was it was an expensive airframe to build. Further when many airlines wanted to buy more, Boeing would only produced them with CDS (common display system IOW side by side screens) rather than the vertical display "classic configuration". That does not seem like a big deal, but it is to the FAA and they decreed that such a fleet mix would require 90 day currency as well as double training foot print on each type of display system. I personally ran into this when I was the initial cadre to check out on the 737NG  which has a CDS. The company thought they would be smart and bought 12 used 737G with the classic configuration glass. Before it was all over I took two rating rides (one in each variant) and had to stay 90 current in each variant. It turned into a huge debacle. So difficult is this issue that when Southwest bought 73N they still had "round dial" 737s. To maintain a common fleet, SWA had the pinout on the CDS changed so it displayed round dials and they flew them "dumb".

That said, Boeing has tried for years to peddle the 737-900 and now the MAX as a 180 seat middle market airplane. Neither of those models are middle market airplanes. Indeed Boeing is now developing a 757 replacement because even they realize the 737  is not a MMA. The -900 is so payload- range limited I was taken off of one in SFO on a flight to ATL for payload limitation and runway performance. That would never happen with a 757. For most airlines the 737-900 on west coast to HNL has turned into a debacle. For most HNL routes, Delta threw in the towel and brought back the 757's.

To correct some things said here. 255,000 pound 757-200 is rare. Most airlines bought them in the 200K level. I've only seen one that was rated above 225K. Equally so a 200K 737 is rare. The numbers you got are the maximum you can buy, but those numbers come with some maintenance and life limit caveats that the airlines are rarely willing to sign on to so they buy lighter weight models.

Could you hang LEAPS on a 757. Don't see why not, but you cannot overcome the airframe building costs disadvantage. Boeing's mistake as pointed out above was relying on the 737 as a MMA model rather than developing a 757 replacement. As for the 737, Boeing will keep building them as long as SWA demand it. 

 

[flyboy0681]

7 minutes ago, GeeBee said:

I will chime in here with some experience. I have thousands of hours in both. I was a Check Airman on both.

The main reason why Boeing ended the 757 was it was an expensive airframe to build.

Great post. Any idea why it was such an expensive airframe to build as opposed to others? I remember reading years ago that some of the cross-section came directly from the 727.

[GeeBee]

More about where it is manufactured than how. 737 fuselages are built in Wichita by a subcontractor and shipped to SEA where as 757 was all SEA built. The 737 fuselages are shipped on special articulated rail cars. They are specially articulated so they can make the turns as they pass through the mountains. I don't believe the 757 fuselage could clear even on special cars. The 757 like the 737NG and MAX fuselages were designed to be one piece assemblies, not section built like the wide bodies.

 

 

 

[StevenL757]

Can’t add anything to @GeeBee‘s posts...all accurate and great info, especially the payload limitations for the -900.  The 75 is all but weight-restricted anywhere it goes.  Delta, for example, sees the value and flexibility and has no plans to retire it (for now) until ~2030.  It’ll be a sad day when it goes. 

[PT20J]

I seem to recall reading that Boeing proposed a new design but the airlines were skittish because of all the problems and delays with the 787 and Boeing came up with the MAX to avoid losing sales to Airbus. Anyone know if that’s true?

Skip

[GeeBee]

No, not really. The airlines have been begging, on their knees for a real 757 replacement. Delta has their checkbook out of their hip pockets and badly wants to be the launch customer.

Boeing has had its head in the sand believing they could use an "on the shelf" product, the 737 until it became clear and they threw in the towel and capitulated to the airlines demands for a real MMA.They thought for a while the MAX might cut it, but the airlines said no and even before the first MAX rolled off the lines, the MMA was on the board.

As far as the MAX goes, two things drove it. LEAP engines and Southwest Airlines. LEAP engines because Airbus was easily mounting them to the A320 series which would give it a 15% SFC advantage over the 737NG. As for Southwest, they have been the driver or the "albatross" around the 737's neck. Back when the NG program was contemplated Boeing wanted a next generation (NG). They wanted to dramatically upgrade the 737 cockpit and systems, all of which would have required a new type rating, most notably changing the motive source in the flight controls. FAR 25 is quite clear that change the flight control system, new type rating (unless you are McDonnell Douglas building the MD-90 then you get a pass because you are broke). So SWA keeps demanding they put new engines and "changing the stereo" in the '57 Chevy so they don't have to depart from their single type fleet. Boeing obliges its largest customer naturally.

When it all comes out in the wash, Boeing will build the 777, 787, MMA and 737. The problem is everyone of these airframes are different enough to incur significant fleet differential costs. Airbus has very carefully cultivated the A320 family which is an enormously flexible platform, the A330 and A350. The A380 was a bust. However one thing all these platforms have is they are a "true family". You really can transition from the A320 to the A330 or even an A380 in about a week. The cockpit of the Airbus have great commonality and system similarity. If Boeing had built a "new 737", they could have drove themselves into a near Airbus like platform with great commonality between their aircraft.It is a gross product mistake on their part.

[jetdriven]

I read a nice article the other day that said Boeing started losing their way when they move the corporate headquarters to Chicago. After that, Boeing focused  on the stock price and gaming shareholders rather than building airplanes. They use the savings from the max program and delaying the new market airplane to purchase $42 billion of stock. Yeah they’re going to spend probably that much on Max woes, and then they still don’t have a new airplane. 
https://www.chicagobusiness.com/opinion/how-boeing-lost-its-way