Boeing starts study towards 737 replacement

killerwhale65 · Post by **killerwhale65** » 02 Mar 2006, 18:40

Boeing announced today it has taken the first formal steps toward a replacement aircraft for the B737. A team has been put together that will study the successor, due to take-off somewhere around 2012-2015. Boeing will start talking to suppliers by mid-2006.

The replacement (currently named Y1) will for sure share some of the technologies used in the 787 (development name Y2). The same research as for the Y1 and Y2 will also be used later on for the development of the Y3 (successor of the 777).

The all-composite body of the 787 is likely to return in the Y1. Furthermore the concept will be based on fly-by-wire, more-electric system architecture, EVS-integrated avionics flightdeck, and a cabin cross-section “wider than A320”. To increase aerodynamics, the Y1 will have increased wingspan, single-slotted flaps, raked and blended-winglet wingtip options, blended fin root and 787-like nose and flightdeck.

Formal launch may be expected in 2008.

SOURCE: Flight International

UltraSonic · Post by **UltraSonic** » 02 Mar 2006, 18:50

Damn no, i'm not really fond of the fly-by-wire system. I want the fly guys back in full control

RC20 · Post by **RC20** » 02 Mar 2006, 20:49

http://seattletimes.nwsource.com/html/b ... ing02.html

As I have been saying for some time, they6 are getting very serious about the Y1 (737RS).

Boeing should have brought out a all new 737RS after the 300,400,500 series. While they are paying price currently, they also skipped a minor improvement generation and will launch it with a major technological advantage.

This is the only hole in the product line. I know other will argue that the 550 seat and up is a gap, but I would disagree. It’s a decision that that segment is either going to be a net looser, or that there is no room for two aircraft. The response is the 747-8, and while that is not 550 seats, it does offer an airline an “option” to use in financial negotiations with Airbus (which means far less profits for Airbus). The offering fills in a hole in the huge gap that Airbus left, and also fills a requirement (even if not a blockbuster seller).

Pressure is now on Airbus, and they do not even have the composite structure experience to respond with (or the electrical architecture)

I still suspect the 2008 date is the likely for serious development and product rolling out the door by 2010.

That’s based on it being fare enough behind the 787 to benefit from what they are finding on the manufacture of it both in composites and the all electrical systems .
Actually it will be more advanced in both regards from that learning experience, not just a knock off copy.
The unknown is if it will use conventional airframe configuration, or break new ground. That depends on if they come up with an alternative that offers significant improvements, and the airlines will buy it.

JoeCanuck · Post by **JoeCanuck** » 03 Mar 2006, 23:42

With a fly-by-wire system doesn't mean the pilot isn't in control. Instead of cables or hydraulics, it just uses wires and servos. You can have a computer programming flight parameters, but you always, (at least in the 777), have the options to leave the computer out of it and fly analog, no computer involved. The wires are just a way to transmit the pilots inputs to the controls.

Andries · Post by **Andries** » 04 Mar 2006, 02:59

UltraSonic wrote:Damn no, i'm not really fond of the fly-by-wire system. I want the fly guys back in full control

If you want a very very simple explanation of what FBW is, you could say that the aircraft is controlled by electrical signals instead of solid cables that transmit force.

On e.g. a 727 the pilots needed their muscles to move the elevator. Now the pilots just pulls back on the stick and the computer measures it and sends the corresponding signal to the elevator controler.

So instead of cables transmitting forces, you get computers sending electrical signals. The "fly guys" as you say it are still in full control ...

FBW has made flying allot safer !
Imagine where an aircraft should pull up as fast as possible, but the pilots don' have enough power to pull back the stick. The result would be a crash because the pilots couldn't pull the stick back enough ...
An FBW pilot would just fully pull back the stick and the aircraft would pull up as fast as it can without breaking appart mid-air. A big advantage if you ask me ...

There is a difference between Airbus FBW and Boeing FBW. An Airbus aircraft cannot be taken outside the flight-enveloppe, whereas a Boeing aircraft can ! Personnally, after getting hours and hours of lessons on Aircraft Technology, I prefer to fly Airbus than Boeing ...

RC20 wrote:As I have been saying for some time, they6 are getting very serious about the Y1 (737RS).

Well, they went ahead with the Y2 (now the 787). The Y1 is now starting to come up and I wouldn't be surprised to see the Y3 in about 10 to 15 years (777-replacement)

All these aircraft, Y1, Y2 and Y3, were part of 1 research project and all have the same technology (the now-called-787-technology).

RC20 wrote:Pressure is now on Airbus, and they do not even have the composite structure experience to respond with (or the electrical architecture)

I would be very carefull when saying such things ... Don't forget that Airbus has got years and years of experience with FBW (all electric).
A300 was the first to incorporate FBW, A320 was the first full FBW aircraft and if you look at the current technology on the A380, I think you'd be surprised how much experience they have ...

Greetz,

Andries

JoeCanuck · Post by **JoeCanuck** » 04 Mar 2006, 21:39

I was under the impression that the 777 remains within the computers flight parameters, the same as the airbus planes. The difference is, (I believe, but am fully prepared to be wrong), is that, if they have to, the pilots can disable the flight control computer and have direct control. They still use fly by wire, just without the computer overlord.

This is a quite useful feature if the computers decide to take a coffee break....not that computers ever fail.

CX · Post by CX » 05 Mar 2006, 00:01

Fly-by-wire is just like brake by wire/steer by wire in cars..... doesn't mean much other than the inputs are transmitted electronically instead of mechanically..

JoeCanuck · Post by **JoeCanuck** » 05 Mar 2006, 16:18

If they wanted to, plane manufacturers could have a computer conrtrol the plane, (in fact they do...it's called autopilot), through the hydraulics or cables.

CX is right. Wires are just another way to get the control inputs to the wings.

Electrically powered controls have a lot going for them...much more reliable and efficient than hydraulics, easier to isolate damaged systems, way lighter and more precise than hydraulics, and a whole lot more.

It's not voodoo. Electric servos have been on Airbusses and fighters for years, (and r/c planes). If they can handle a war environment, civilian stuff is a piece of cake in comparison.

Andries · Post by **Andries** » 05 Mar 2006, 19:52

JoeCanuck wrote:Electrically powered controls have a lot going for them...much more reliable and efficient than hydraulics, easier to isolate damaged systems, way lighter and more precise than hydraulics, and a whole lot more.

Fly by wire and hydraulics are not opposites, on the contrary, they are a team ! As electrical systems can't transmit force, they use those systems to control the hydraulic valves. So all that talk about it being much more reliable and efficient than hydraulics is just b*llsh*t ! A Fly By Wire plane without hydraulics wouldn't even get off the ground !
Flaps, landing gear, gear brakes, ailerons, speedbrakes, gearbay doors, ... All controled by hydraulics whose's valves are controled by the Fly By Wire system !

Greetz,

Andries

Knight255 · Post by **Knight255** » 05 Mar 2006, 20:42

Imagine where an aircraft should pull up as fast as possible, but the pilots don' have enough power to pull back the stick. The result would be a crash because the pilots couldn't pull the stick back enough ...
An FBW pilot would just fully pull back the stick and the aircraft would pull up as fast as it can without breaking appart mid-air. A big advantage if you ask me ...

Can you give me some specific scenarios?? I can think of a few very embarrassing accidents that Airbus had whilst demonstrating their technology. I'm not starting an A vs. B war here, Airbus has done a good job of sorting out the early bugs with their FBW systems and training their pilots. I strongly disagree with you though. No offense though, we're all entitled to our own opinion. This is my biggest beef with Airbus and why I refuse to fly one of their planes as a pilot. I have been a pilot for over 6 years (and I'm only 21) and the thought of a computer overriding my command is just scary to me. I am trained to be pilot-in-command, and by God I will act as one! I am not afraid of computers, far from it, I was brought up in the computer generation!! It is the pilot-in-command's ultimate responsibility to fly the plane, it requires finesse and skill. A pilot who relies on a computer to prevent them from being stupid is not a pilot, but a glorified bus driver!!!!

Andries · Post by **Andries** » 05 Mar 2006, 22:38

Knight255 wrote:This is my biggest beef with Airbus and why I refuse to fly one of their planes as a pilot. I have been a pilot for over 6 years (and I'm only 21) and the thought of a computer overriding my command is just scary to me.

The computer does not override anything unless it becomes very dangerous. If the pilot would want to make a manouvre that would take the aircraft out of the flight enveloppe, then the computer would interact, otherwise the computer is only there to control the FBW system and ensure a smooth flight with the Pilot still in command

A pilot never intends to take his/her aircraft outside the flight envelope, unless he/she is suicidal ! So the computer taking over at that point is only in order to save the lives on those on board and to save the airframe ...

Knight255 wrote:I can think of a few very embarrassing accidents that Airbus had whilst demonstrating their technology.

If you are thinking about the Air France A320 crash, that was Pilot-error.

See : http://aviation-safety.net/database/rec ... 19880626-0
And : http://aviation-safety.net/investigatio ... acf296.php

Knight255 wrote:Can you give me some specific scenarios??

Hmmm, let me think ... STALL !
Imaging an aircraft flying at low speed at very high angle of attack, ok ?
Suddenly, the pilot pulls the stick back 100% ...

What would a non-FBW aircraft do ? Pitch nose up and eventually go down if the altitude isn't high enough to recover from the stall.

What would an FBW aircraft to ? Go to max. angle of attack without going into stall. If I am not mistaking, the computer will even give a command to the engines to give some more power to stay away from the stall zone ... I am not sure about the latter, but I will contact my teacher in aviation-technology about this. I am though 100% sure you can't pull an Airbus aircraft (A320 and later) into a stall !

Greetz,

Andries

Knight255 · Post by **Knight255** » 05 Mar 2006, 23:01

You're still ignoring the fact that it should be the pilot's responsibility to keep the plane within the flight envelope, not the computer. In regards to a stall, have you ever heard of a stick-shaker/stick-pusher, a convenience found on almost all commercial aircraft?? Why would a experienced airline pilot have the urge to pull the stick back 100%?? I'm curious because you're seriously coming up with some really ridiculous scenarios here. If there is an immanent stall, the pilots are trained to reduce AOA and hit the TOGA buttons. Additionally, sometimes it's necessary to stall the airplane, do you know (aerodynamically speaking) what a full-stall landing actually is?? In regards to the A320 crash, I acknowledged that it was in part pilot error. However, there was an computer-pilot interface problem as well.

I'm an Aviation Human Factors major, and we've analyzed this crash many times. I admit to being

fftopic: but I hate this myth that FBW planes are safer than non-FBW planes. Given a well trained pilot, both are safe!!

Andries · Post by **Andries** » 06 Mar 2006, 01:08

Knight255 wrote:I admit to being fftopic: but I hate this myth that FBW planes are safer than non-FBW planes.

I didn't say they were safer, I said I prefered them for some reasons ...

Knight255 wrote:You're still ignoring the fact that it should be the pilot's responsibility to keep the plane within the flight envelope, not the computer.

Yes, you are 100% correct, but then again, if the pilot would stay within the boundary's of the flight envelope, the stick-shaker wouldn't be neccesairy too ...

Knight255 wrote:Why would a experienced airline pilot have the urge to pull the stick back 100%?? I'm curious because you're seriously coming up with some really ridiculous scenarios here.

Well pilots are only human and humans tend to make mistakes (those chances are even higher when under stress). I was just looking for a scenario to explain what I meant. The computer is there for when the pilot makes a critical mistake ...
I'm not saying the computer can make sure no mistakes are made, they are just there to help prevent them as many many crashes are often cause by "pilot error" !

Knight255 wrote:do you know (aerodynamically speaking) what a full-stall landing actually is??

I have never heard of it, but I assume that it is a landing at max. AOA and lowest possible airspeed. If my assumption is correct, then that condition is still within the flight envelope and the computer would not react . I find it hard to believe you would actually go into an effective stall during approach/landing ... cause this would mean that you lose your lift as the air doesn't flow nicely over the top of the wing anymore ...
If my assumption is incorrect, please fill me in on this procedure

I am allways willing to learn !

Knight255 wrote:Given a well trained pilot, both are safe!!

I agree with you on that for the full 100% !

Greetz,

Andries

JoeCanuck · Post by **JoeCanuck** » 06 Mar 2006, 01:18

So all that talk about it being much more reliable and efficient than hydraulics is just b*llsh*t ! A Fly By Wire plane without hydraulics wouldn't even get off the ground !
Flaps, landing gear, gear brakes, ailerons, speedbrakes, gearbay doors, ... All controled by hydraulics whose's valves are controled by the Fly By Wire system !

Greetz,

Relax.....lighten up a tad....no need to shout. We can't all be experts. Sometimes, I take a guess. No big deal.

boeing797 · Post by **boeing797** » 06 Mar 2006, 04:15

JoeCanuck wrote:So all that talk about it being much more reliable and efficient than hydraulics is just b*llsh*t ! A Fly By Wire plane without hydraulics wouldn't even get off the ground !
Flaps, landing gear, gear brakes, ailerons, speedbrakes, gearbay doors, ... All controled by hydraulics whose's valves are controled by the Fly By Wire system !

Greetz,

Relax.....lighten up a tad....no need to shout. We can't all be experts. Sometimes, I take a guess. No big deal.

Agree with you. B737 is not equipped with FBW but still has good safety record and sold well compared to A320. Airbus has years of experience in FBW and has developed a great FBW system for A380 as it claims but A350 with FBW developed for A380 has a hard time to catch up with B787 in terms of sales. So either Airbus FBW system is overrated or airlines don't care much.

Ciao

Knight255 · Post by **Knight255** » 06 Mar 2006, 05:55

I have never heard of it, but I assume that it is a landing at max. AOA and lowest possible airspeed. If my assumption is correct, then that condition is still within the flight envelope and the computer would not react . I find it hard to believe you would actually go into an effective stall during approach/landing ... cause this would mean that you lose your lift as the air doesn't flow nicely over the top of the wing anymore ...
If my assumption is incorrect, please fill me in on this procedure icon_wink.gif I am allways willing to learn !

You said that the computer would not allow the airplane to stall now it will?? It is very rarely used technique for landing. Typically it is used on VERY short runways when slow groundspeed is needed and the plane needs to touchdown quickly with no floating (KSNA for example). A typical airliner will fly an approach at Vref +10 and touchdown right around Vref (1.3 times Vso if I am not mistaken). This is done to create a smoother touchdown and avoid scaring the pax with the jolt of the landing.

On with the real topic, I commend Boeing for taking back the initiative in creating innovations in the airline industry. My one concern is where the capital is coming from to fund such a project?? The 787 is by no means cheap, and to already be talking about a new plane is risky in my opinion. On the other hand, if Boeing seems to keep Airbus in the reaction mode, not action, it will be good for Boeing's business.

Fuji-Monster · Post by **Fuji-Monster** » 06 Mar 2006, 09:39

Hello,

The FBW (like 320) is not overriding the pilot's commands.
It just provides some extra protections against overload, overspeed, bank angle and stall.

The pilot still has full command within the flight envelope and the FBW won't allow you to go out of that envelope.
Of course, no pilot should look for the bounderies of this envelope but distraction or just straight forward error are always a possibility.

Only in case of stall; there is an automated spool-up of the engines.

Greetz

Andries · Post by **Andries** » 06 Mar 2006, 12:24

Knight255 wrote:You said that the computer would not allow the airplane to stall now it will??

I didn't say it will go into a stall. I said I found it hard to believe.

As said before, I went to my teacher in Aviation Technology and he explaned me what the procedure is. It is perfectly possible to do this with for example a cessna 172, a piper, ... but not with an Airbus (if all systems are working like they should). When an Airbus tends to go into a stall, the computer will automatically apply more power to keep it out of stall !

JoeCanuck wrote:Relax.....lighten up a tad....no need to shout. We can't all be experts. Sometimes, I take a guess. No big deal.

1) I am very relaxed
2) I am not shouting
3) Offcourse we can't be expert
4) Sometimes you take a guess, no problem. The problem I had with the statement was that it was mentioned as being the truth. It is allways safer to say "I think this and that" instead of "its like this and that" unless you are absolutelly sure of what you are saying.

No hard feeling,

Greetz,

Andries

Fuji-Monster · Post by **Fuji-Monster** » 06 Mar 2006, 17:01

The A320 will not stall when all flightcomputers are working properly.
It will keep its minimum flying speed and will descend with a certain rate of descend.
Even when you pull aft on the stick; it will continue its descend with its minimum speed.
You will need thrust before it will ever climb again.

Andries · Post by **Andries** » 06 Mar 2006, 18:24

Fuji-Monster wrote:The A320 will not stall when all flightcomputers are working properly.
It will keep its minimum flying speed and will descend with a certain rate of descend.
Even when you pull aft on the stick; it will continue its descend with its minimum speed.
You will need thrust before it will ever climb again.

Well, there you have the answer, and this time from an expert

Greetz,

Andries