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-   -   Boeing Considers Developing a 757-PLUS Instead of New Mid-Market-Airplane Dubbed 797 (https://www.pprune.org/rumours-news/632317-boeing-considers-developing-757-plus-instead-new-mid-market-airplane-dubbed-797-a.html)

beachbumflyer 11th May 2020 22:02


Originally Posted by Pugilistic Animus (Post 10779126)
I think that the main issue with a COMBI is smoke abatement and fire suppression

But I think that's the same with any cargo airplane. Correct me if am wrong.

Pugilistic Animus 11th May 2020 22:19


Originally Posted by beachbumflyer (Post 10779664)
But I think that's the same with any cargo airplane. Correct me if am wrong.

It's the same and it's different at the same time. The airplane must pass the certification process for carrying cargo but it's very difficult to certify a COMBI due to proximity to the passengers and some of the procedures to starve fires of oxygen would be quite deleterious and ultimately fatal

tdracer 11th May 2020 22:23


Originally Posted by Pugilistic Animus (Post 10779676)
It's the same and it's different at the same time. The airplane must pass the certification process for carrying cargo but it's very difficult to certify a COMBI due to proximity to the passengers and some of the procedures to starve fires of oxygen would be quiet deleterious and ultimately fatal

Further, while they don't talk publicly about it much, the regulators treat cargo operations as more 'expendable' than passenger operations. Examples being the different treatment of Li batteries, and the exemption of cargo aircraft with more than two engines from the requirements of EDTO.
As a result, the fatal accident rate of cargo operations is significantly higher than it is for passenger operations.

lomapaseo 12th May 2020 00:38


Originally Posted by tdracer (Post 10779684)
Further, while they don't talk publicly about it much, the regulators treat cargo operations as more 'expendable' than passenger operations. Examples being the different treatment of Li batteries, and the exemption of cargo aircraft with more than two engines from the requirements of EDTO.
As a result, the fatal accident rate of cargo operations is significantly higher than it is for passenger operations.

I don't argue with your safety statistics but;

I don't like your examples. Association does not equal causation

There are plenty of other contributing factors that might be considered in the actual causal chains,

tdracer 12th May 2020 02:00

Loma, I'm not talking cause and effect, I'm pointing out evidence that the regulators apply a different standard of safety to cargo operations than they do to passengers. Why else would the rules be different - and they are different as pointed out by my two examples.

Anti Skid On 12th May 2020 03:10


Originally Posted by tdracer (Post 10777682)
Not sure about it being bollocks - particularly this bit:

I think this is what really hurt the 757-300 - it was simply too long for a single aisle. This made turn times horrible, and on-board service a nightmare - I sat near the back of a 757-300 one time, after we landed I timed it - it took 10 minutes after the door opened before there was even movement where I was sitting (I flew trans-Atlantic on a DC8-60 way back when - it had the same problem).
Direct operating costs per seat mile for the -300 were good, but it took so long to turn that it took a serious hit for productivity. Single aisle becomes problematic when you get much over 200 seats - twin aisle simply works better when you get much above 200 seats.

I think you missed one little aspect; I once travelled on an A319 operated by Air Canada, with atrocious seat pitch. At one point the queue for the toilets, both at the rear, was 50% the way down the aisle. Had the seat pitch allowed 20 less seats this issue would have been better. Post Covid will be see better seating? Here's hoping

Midland 331 12th May 2020 17:33


Originally Posted by Turbine D (Post 10778731)
Should Boeing decide to lengthen the current 757, I hope they do a better structural design than Douglas did in lengthening the DC-8 to the DC-8-61. If you sat in one of the rearmost row of seats and the aircraft was experiencing moderate turbulence, it gave one the feeling the rear section was going to torque off from the sections more forward, it was so visibly noticeable. It scared the heck out of unknowing passengers...

The same in the "75" in certain crosswind conditions. I once nabbed the final seat on a Manchester Shuttle when on a staff ticket, the aisle on the last row, and watched the window pillar in the cockpit move from side to side as we bumped and crabbed onto 06 at Manchester. Interesting views with that cockpit door wide open. It was a while ago...

My former boss at SAS, Willie Mason, used to work on traffic at Prestwick, and mentioned that crews were asked not to park with the nose wheel at an angle on a DC8-63 as occasionally certain doors wouldn't open.

fitliker 12th May 2020 23:24

Zone loading is now the norm . That should cut loading time down . Not quite as quick as playing music and telling everyone grab a seat when the music stops , preferably you own seat Joe ! . We have all played that game and would make last person seated buy the rest of the pax coffee :)

Modern computer Zone Loading and music would help . I would suggest dance music like
Manu Debango Soul Makossa . Or the Jeopardy theme would get people moving .
A good theme music might bring some joy back into the journey process .

Zone Loading saves time .

Peter47 15th May 2020 07:53

Agree about zone loading. Even better if you also load from the back as the locos do, but also KLM at AMS through airbridges. A lot of 753s are used on longer routes likes West Coast to Hawaii where loading times are less important.

The DC8 60s series were good aircraft from a cost viewpoint. The obvious way forward was to replace four engines with two more efficient ones, which gives you, err, the 753. There's a definite comfort gain in having twin aisles though.

esscee 15th May 2020 09:18

Twin aisles, Zone boarding and also make use of the rear doors too, all of which ought to be a minimum design feature. If it saves time and makes pax on/off more efficient then that is a bonus as well.

SWBKCB 15th May 2020 20:38

777-300 is a lot longer than a 757-300 - granted a greater proportion of premium seats and mainly long haul so turnround times less critical, but can't see that being a twin aisle makes that much difference to loading/unloading speeds?

DaveReidUK 15th May 2020 21:45


Originally Posted by SWBKCB (Post 10783662)
but can't see that being a twin aisle makes that much difference to loading/unloading speeds?

Gosh, that's going to be a tricky one to explain.

procede 15th May 2020 22:54


Originally Posted by DaveReidUK (Post 10783717)
Gosh, that's going to be a tricky one to explain.

Not really: Fewer seats per aisle. A 737 has 6, a 767 has 3.5 (2-3-2).

tdracer 15th May 2020 23:15


Originally Posted by procede (Post 10783748)
Not really: Fewer seats per aisle. A 737 has 6, a 767 has 3.5 (2-3-2).

Pretty sure DR was being sarcastic...

Bend alot 17th May 2020 01:14

Is now not the perfect time for Boeing to come up with a complete new family of aircraft?

Selling any new aircraft in the next few years in any numbers will be pretty tough.
The government will not let it fail.
The MAX has issues.
The 747 is pretty much over.
They lack a small regional aircraft.

A complete new series of clean sheet aircraft with much in common could be a long term win & it could be possible to meet the regs for comi configurations on a clean sheet.

SWBKCB 17th May 2020 07:09


Originally Posted by procede (Post 10783748)
Not really: Fewer seats per aisle. A 737 has 6, a 767 has 3.5 (2-3-2).

United 757-300 has about 35 rows of 3-3, EK operates 777-300 with about 35 rows of 3-4-3? So is the 757-300 really too long?

Wickerbill 17th May 2020 07:44


Originally Posted by Bend alot (Post 10784624)
Is now not the perfect time for Boeing to come up with a complete new family of aircraft?

Selling any new aircraft in the next few years in any numbers will be pretty tough.
The government will not let it fail.
The MAX has issues.
The 747 is pretty much over.
They lack a small regional aircraft.

A complete new series of clean sheet aircraft with much in common could be a long term win & it could be possible to meet the regs for comi configurations on a clean sheet.

I think the​ problem for Boeing is the cost; It was hoping to milk the 737 Max whilst recouping the last part of development for the Dreamliner and develop the 777X. It has some awful cost over runs on its military programmes​, so cash for a clean sheet was limited even before Covid19. Now with sales (probably) on the floor, need for government support just to carry on, the ability to develop a clean sheet design from resources available to them ain't gonna happen. The likely collapse in demand will put Airbus in the same spot, even though they don't have the same number of problem programmes that Boeing have.
​​​​​​Maybe in 3 years time things will be easier?


Less Hair 17th May 2020 13:08

On a positive note there is no revolutionary new engine available right now that would be required before starting any uber-competitive new design. So waiting five years or so for it to be ready will do no harm. At the same time oil is too cheap now to trigger much demand for more efficient new airplanes. There are just too many old ones available for cheap now and they will be during the next few years.

procede 17th May 2020 14:02


Originally Posted by Less Hair (Post 10785039)
On a positive note there is no revolutionary new engine available right now that would be required before staring any uber-competitive new design.

Geared turbofan?

Less Hair 17th May 2020 19:32

True but this is already available.
"We" would need something newer and better to top some A321neo with today's latest GTF and PIP by a few percent engine wise. Possibly something with huge bypass ratio and diameter? If a new engine can be integrated from scratch more efficencies will be gained. CFRP wings (maybe a high wing layout?) and fuselage and these new engines with some smart cockpit might make it work one day. I'd say before the late 2020s no new engine like the one needed will be available.


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