CAA bans Boeing 737 max 8

Your above is even more cutthroat if you consider that for a long time Boeing was able to undercut Airbus in the single aisle market because there was no competitor to the 74 and so a little mark up there subsidised 73 production.

Seem to recall the CAA mandated a larger fin as well to bring it on the UK register.
@Toastie - because hes the man that will know and will tell me if im confused (or talking bollocks)
Pass. Bigger rudder I think it was?

On the subject of rudders and Boeing 737 NGs, a number were lost early on because they unaccountably rolled on their back and speared in. All they knew was that an uncommanded rudder input was made, always on approach. In jets you never use the rudder in flight except to kick off drift in the flare on touch down or if an engine fails to kick off the asymmetric thrust derived yaw (the flat, skidding movement about the vertical axis, think sticking a knitting needle through the roof vertically, move nose left, arse goes right). Investigators were completely stumped and of course the pilots weren’t around to offer any kind of explanation.

At this point let’s take a break and look at the old schoolboy conundrum where they’re asked to explain how a man came to be found hanging in a completely bare room with the door locked on the inside? The only feature of the room is a drain in the floor. Have a think.

Anyway, the investigators finally established that water in the hydraulic actuators controlling the rudder was freezing at high altitude in flight. A device called the Yaw Damper is designed to to damp out the yaw that occurs naturally in flight (see above). It in turn is linked to a device called Rudder Ratio that reduces rudder movement with increasing speed because the faster you go, the less control input you need to achieve the same result. It’s the same principle as the steering on your car, you need full lock to park it at low speed, try full lock at 70mph and it gets exciting.

So these systems were demanding a small input at high speed but nothing was moving because it was iced up. So they kept trying. They were still trying as the aircraft descended to warmer air but now the Rudder Ratio was demanding a bigger input because the aircraft was slower ready for landing. The ice melted and suddenly everything unlocked and put in a massive rudder input, called a Rudder Hardover which caused the aircraft to roll on its back. The crew were correctly trying to put opposite rudder in but to no avail as their input was being fought by the system.

Finally after I think 3 total hull losses it happened again but the pilot in this case had considerable high performance aerobatic experience and managed to fly through it using unconventional control inputs. His testimony provided the clue that unlocked the case.

In response, Boeing quietly retrofitted a device called a Force Fight Monitor and claimed it was nothing to do with the above events.

My point here is that the NG actually killed more people and had a redesign of the offending system and went on to be a best seller. I predict history will repeat itself.

And the bloke hanging? He’d walked into the room with a big block of ice and a noose, locked the room from the inside, put the noose round his neck stood on the block of ice and waited for the ice to melt. As the ice melted he descended, hanging himself. The melted ice ran out of the drain and the floor dried leaving no evidence.
 
that would be the airlines terrified of an Airbus monopoly if Boeing took a development holiday to get its 797 built while soldiering on with building bargain priced NGs in the meantime?
Their are a more than few CEOs who aren’t in any position to throw mud at Boeing. they will do anything now up to and including sucking Seattle dick to get a new low range plane to out Airbus Airbus out the door ASAP.
the airlines wanted a bigger better 737, Boeing gave them what they wanted, even though they knew it was the wrong answer.
Oh God
 
VFW614 walt
Had a cabbie in one as a kid, late 70s. It was a good plan to limit FOD ingestion by engines but came unstuck because regular maintenance was more regular than FOD damage and the maintenance was a pain because access to the engines was difficult. There was also a big issue with passenger perception. I guess the world wasn’t ready for something that “didn’t look right”?

Was oblivious to the Honda Biz Jet! I wonder how /if they get round the above problems?
 
Had a cabbie in one as a kid, late 70s. It was a good plan to limit FOD ingestion by engines but came unstuck because regular maintenance was more regular than FOD damage and the maintenance was a pain because access to the engines was difficult. There was also a big issue with passenger perception. I guess the world wasn’t ready for something that “didn’t look right”?

Was oblivious to the Honda Biz Jet! I wonder how /if they get round the above problems?
Ooh. Fair one. Biz jet might have far fewer hours and cycles annually ,longer engine mtbo, so having to get it off the wing might be measured in years ? Aesthetically? I suppose biz jet flights are short and looking out the window might not figure in companies costings.
 
Ooh. Fair one. Biz jet might have far fewer hours and cycles annually ,longer engine mtbo, so having to get it off the wing might be measured in years ? Aesthetically? I suppose biz jet flights are short and looking out the window might not figure in companies costings.
No idea. Hope it works out though, there’s room in the market for smaller players, look at how Embraer and Bombardier have fared? It also helps that the Honda thing and the above two makers have produced some lovely looking machines.
 
Pass. Bigger rudder I think it was?
Yeah Rudder sounds more likely

I know the MD902 has the dustbin* extension to the tail boom as UK CAA weren't happy with the control authority in certain conditions as designed
Im sure it was a similar issue viz 737 on introduction and rudder sounds more likely

The Campaign** against Aviation are nothing if not thorough and its not just Structures - Bringing (Old) Dauphins onto the UK registers a bugger as you have to modify the electrical system for UK compliance -

*It Literally does look like a dustbin

** Its in the serious bit - other C words are available
 
With more than 400 x 737 MAX aircraft parked-up all around the production facility, including on employees’ staff car-parking areas, at the Renton factory, and also at a civilian airfield.

And, it is understood, that at the end 2019, a total of 791 x 737 MAX were already with airlines - all of which it is understood have also been grounded.


What is to be done with all of them . . . ?

[Continued . . .]

A). Re-write the computer programmes, and/or train pilots not to fly the aircraft as instinctively - as they would have done in the past - and, to allow the computer to do its work?

It is understood that this Option A), is the favoured one, with which Boeing are progressing.

Whilst this might eventually satisfy the FAA, CAA, etc., one has to wonder if the reliance on electrically powered computers to control an inherently unstable passenger aircraft, will give confidence to potential customers/passengers.

This possible suggested solutions, would involve Boeing persevering with the unreliable, discredited “Manoeuvring Characteristics Augmentation System” (MCAS) computer programme from the 737 MAX.
 
Last edited:
Had a cabbie in one as a kid, late 70s. It was a good plan to limit FOD ingestion by engines but came unstuck because regular maintenance was more regular than FOD damage and the maintenance was a pain because access to the engines was difficult. There was also a big issue with passenger perception. I guess the world wasn’t ready for something that “didn’t look right”?

Was oblivious to the Honda Biz Jet! I wonder how /if they get round the above problems?
I must admit I do look at it and think if you've gone with a T tail and your sticking them there you might as well have just stuck them at the aft end of the fuselage
 
With more than 400 x 737 MAX aircraft parked-up all around the production facility, including on employees’ staff car-parking areas, at the Renton factory, and also at a civilian airfield.

And, it is understood, that at the end 2019, a total of 791 x 737 MAX were already with airlines - all of which it is understood have also been grounded.


What is to be done with all of them . . . ?

[Continued . . .]

B). Re-engine the aircraft with an earlier - proven - type of engine/pylon (***), even if this is less fuel efficient?
(***) Such as the CFM International CFM56-7 series engine, successfully used on the predecessor Boeing 737 Next Generation (737NG, or 737 Next Gen), of which it is understood (at 30 November 2019), a total of 7,092 x 737NG have been ordered, and of which 7,046 have been delivered!!

This could/would be a possible immediate/mid-term solution, and possible long term/permanent solution for some . . the “737 MAX Lo”.

Low cost. Low aircraft height. Low risk. Low(er) fuel efficiency.

At least such a (temporary?), measure would put hundreds of aircraft back into service; allow others to be delivered; relieve timetables; begin to earn some revenue with which to pay lease premiums; and, help airlines/Boeing to “bed-in” and mature all the other new “systems” associated with the 737 MAX.

It would be a serendipitous coincidence if the (temporary) replacement 737 Next Gen engine/pylon, bolted to exactly the same bolt-hole position on the wing of the 737 MAX. However, one can imagine the designer’s inclination to COPY&PASTE such a proven, established, feature/detail.


NOTE: using the 737 Next Gen engine and shorter pylon, on the 737 MAX, does not mean the re-engined 737 MAX reverts to, becomes, a 737 Next Gen.

The 737 MAX, includes many other developments over, improvements to, the earlier 737 Next Gen. These include aerodynamic changes such as new, different, distinctive split-tip winglets, and airframe modifications.

“Other improvements include a re-contoured tail cone; revised auxiliary power unit inlet and exhaust; aft-body vortex generators removal; and, other small aerodynamic improvements”.

“The 8 in (20cm) taller nose-gear . . ; the main gear and landing gear and supporting structure are beefier; fuselage skins are thicker in some places . . . Rockwell Collins will supply four x 15.1 inch (380mm) landscape liquid crystal displays 9LCD), as used on the 787 Dreamliner”.

More visible, obvious, to passengers “The 737 MAX (features) the ‘Boeing Sky Interior’ with overhead bins and LED lighting based on the Boeing 787’s interior”.

This possible suggested solutions, would allow Boeing to totally remove, “wipe”, the unreliable, discredited “Manoeuvring Characteristics Augmentation System” (MCAS) computer programme from the 737 MAX.
 
With more than 400 x 737 MAX aircraft parked-up all around the production facility, including on employees’ staff car-parking areas, at the Renton factory, and also at a civilian airfield.

And, it is understood, that at the end 2019, a total of 791 x 737 MAX were already with airlines - all of which it is understood have also been grounded.


What is to be done with all of them . . . ?

[Continued . . .]

D). Employ lengthened landing legs to lift the whole aircraft the required amount, that would then allow Boeing to re-mount, re-locate, the new fuel-efficient, engines more rearwards, on conventionally short(er) pylons, that bring 737 MAX CoG (centre of gravity), back to the benign, neutral, position of earlier 737 Next Gen aircraft.

This would be a long term/permanent solution . . . the “737 MAX Hi”.

High(er) cost. High(er) structural/component changes. High aircraft height . . . . High(er) fuel efficiency.

To accommodate an even still larger engine, it was proposed (in mid-2016), for the MAX 10, that stronger wings, and longer telescoping landing gear, be adopted.


NOTE: “ . . the proposed MAX 10 included . . . semi-levered landing gear design (which) has a telescope oleo-pneumatic strut with a down-swinging lever to permit a 9.5 inches (24cm) taller gear. Driven by the existing retraction system, a shrink-link mechanical linkage mechanism at the top of the leg - inspired by carrier aircraft designs - allows the gear to be drawn in and shortened while being retracted into the existing wheel well . . ”.

If it is feasible, acceptable to lift the 737 MAX 10, yet higher . . . it is suggested that if the new MAX 10’s longer telescoping landing gear, was to be adopted for all the earlier 737 MAX variants . . . this would/should allow the 737 MAX’s fuel efficiency CFM International LEAP-1B engines, to be then repositioned (using a similar pylon to that on the 737 Next Generation), more rearwards, but still BELOW the wing, on conventionally short(er) pylons, that bring 737 MAX CoG (centre of gravity), back to the benign, neutral, position of earlier 737 Next Gen, aircraft?

This possible suggested solutions, would allow Boeing to totally remove, “wipe”, the unreliable, discredited “Manoeuvring Characteristics Augmentation System” (MCAS) computer programme from the 737 MAX.
 
Ooh. Fair one. Biz jet might have far fewer hours and cycles annually ,longer engine mtbo, so having to get it off the wing might be measured in years ? Aesthetically? I suppose biz jet flights are short and looking out the window might not figure in companies costings.
Will still need Daily and weekly inspections so its going to be a bugger for that at the very least.
As for MTBO - Probably little or no different and potentially worse in terms of hours. Calender wise you could be right that the lower hours translates into more time between removals - but its possible some items are lifed I terms of age as well as hours - I couldn't tell you - to be honest at this point things are getting dirty and I go look at squiggly amps
 
Yeah Rudder sounds more likely

I know the MD902 has the dustbin* extension to the tail boom as UK CAA weren't happy with the control authority in certain conditions as designed
Im sure it was a similar issue viz 737 on introduction and rudder sounds more likely

The Campaign** against Aviation are nothing if not thorough and its not just Structures - Bringing (Old) Dauphins onto the UK registers a bugger as you have to modify the electrical system for UK compliance -

*It Literally does look like a dustbin

** Its in the serious bit - other C words are available
Sadly the CAA has lost much of its expertise and with it, it’s teeth. It’s just a branch office for EASA now. I can’t help but think this wouldn’t have happened 15 years ago. We all laugh about them being the Campaign Against Aviation because it was hard to get anything past them but actually that’s the whole point of a Regulator.

Manufacturers and airlines no longer respect them, possibly they used to fear them a bit. Safety is a casualty of that.
 
B). This could/would be a possible immediate/mid-term solution, and possible long term/permanent solution for some . . the “737 MAX Lo”.

NOTE: using the 737 Next Gen engine and shorter pylon, on the 737 MAX, does not mean the re-engined 737 MAX reverts to, becomes, a 737 Next Gen.
Your point in blue not with standing - I think id go with NG Plus thus avoiding the max name in the shorter term and sidestepping customer enquires neatly - no sir its not a max its a late model ng
 
Sadly the CAA has lost much of its expertise and with it, it’s teeth. It’s just a branch office for EASA now. I can’t help but think this wouldn’t have happened 15 years ago. We all laugh about them being the Campaign Against Aviation because it was hard to get anything past them but actually that’s the whole point of a Regulator.

Manufacturers and airlines no longer respect them, possibly they used to fear them a bit. Safety is a casualty of that.
Still have authority for national assets eg police aviation - which at least has kept a core obstructiveness in situ bet like MPA seed corn.

Ive long argued I felt the CAA was the best model - FAA to close to industry the DGAC was to politically influenced - the CAA hated everyone and answered to no one - They were god and it was right. Best of all they were stuffed full of professionals - not simply bureaucrats - so could comprehend spirit not word and alternative compliance.
They also new all the tricks - so hard to bluff them


Edit - I suppose it will be a Brexit plus that once again they will be free to spread fear and Dread from Gatwick to Inverness
 
(...) My point here is that the NG actually killed more people and had a redesign of the offending system and went on to be a best seller. I predict history will repeat itself. (...)
The most likely medium to long term consequences for Boeing will be the financial losses will put a crimp in their R&D budget, and the extra checks, tests, and re-tests of their software and systems (how the software interacts with the hardware) will slow down development there as well, possibly putting them further behind Airbus in new product development.

The financial losses include not only the direct losses from the grounding, but also they have reportedly been forced to offer various discounts to prospective customers as well.

The big black eye in terms of PR for Boeing in all this isn't that they made a design mistake, it's that the mistake was made through cutting corners to get the product out the door sooner, and also that they tried to avoid making any proper response to the problem until being dragged kicking and screaming into doing so. There was a news story in the past few months which said that the rot was deep in Boeing, and it would take a decade to turn things around.
 
The most likely medium to long term consequences for Boeing will be the financial losses will put a crimp in their R&D budget, and the extra checks, tests, and re-tests of their software and systems (how the software interacts with the hardware) will slow down development there as well, possibly putting them further behind Airbus in new product development.

The financial losses include not only the direct losses from the grounding, but also they have reportedly been forced to offer various discounts to prospective customers as well.

The big black eye in terms of PR for Boeing in all this isn't that they made a design mistake, it's that the mistake was made through cutting corners to get the product out the door sooner, and also that they tried to avoid making any proper response to the problem until being dragged kicking and screaming into doing so. There was a news story in the past few months which said that the rot was deep in Boeing, and it would take a decade to turn things around.
Some background...

 

Latest Threads

Top