Has everyone suddenly forgotten how to build airplanes?
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It's an interesting point - how come Airbus gets away with this exemption just because the stick is on the side, while Boeing are required to create perfectly progressive stick feedback force, all the way to the extremes of the envelope, and in trying to meet the requirement, create MCAS? Progressive pitch force is a major design headache, from single engine homebuilts, right through to airliners. Meanwhile there have been several Airbus incidents, arguably attributable to the lack of stick force feedback.
So, where did the process break down? A poor envelope specification up front? Or marketing caving in to a customer to cram in just one more row of seats? The article says Lufthansa is affected rather than all customers. So I suspect it's the latter.
Good questions. The reduced C of G envelope that EASA has imposed obviously applies to all A320neo and A321neo aircraft, but it could well be that only Lufthansa's particular LOPA causes them a problem as a consequence.
Only half a speed-brake
When I trim my Airbus in DCT law for clean speed and then bring towards stall using a pitch up command on the stick, there is progressive force that needs to be overcome. No issue.
Next.
Oh, wait. If I have a stroke mid-way and let go off the stick, the nose drops down and does not hang up, or - heaven forbid - keep raising.
For those interested in the particular CG restriction on A320, please see my comment on the A321 thread.
Speaking of which: if the manufacturer discovers on a test rig something about the pitch response is not aligned with the book exactly, WITHOUT any prior in-service event or SIM observation, just by doing their QA homework properly, that is actually how you DO build an aeroplane. Not faultless, but responsible is the key word.
If I wanted to be mean, a little note would slip about how you can fully trim the Bus manually in and out of all settings at all corners of the envelope. But I am a much nicer person than that.
Next.
Oh, wait. If I have a stroke mid-way and let go off the stick, the nose drops down and does not hang up, or - heaven forbid - keep raising.
For those interested in the particular CG restriction on A320, please see my comment on the A321 thread.
Speaking of which: if the manufacturer discovers on a test rig something about the pitch response is not aligned with the book exactly, WITHOUT any prior in-service event or SIM observation, just by doing their QA homework properly, that is actually how you DO build an aeroplane. Not faultless, but responsible is the key word.
If I wanted to be mean, a little note would slip about how you can fully trim the Bus manually in and out of all settings at all corners of the envelope. But I am a much nicer person than that.
Expecting a pilot who had 250 hours years before he started flying Airbus airplanes to actually know how to fly a normal airplane is a little much. I flew the A320 and loved it, but I spent years flying most of the Boeings first. There is a huge difference.
I cannot understand how being a pilot of an FBW airliner is any lesser than a cables and pulley airliner pilot.
Does anyone criticise F16 or current FBW fighter pilot as being a lesser pilot than an F4 or A4 pilot?
Strange logics (no pun intended).
You are there to fly/operate a flying machine that 'makes money' for 'shareholders'. If you're lucky you have an aeroplane that makes doing that day in, day out easier and 'backs you up'.
If you wanna go 'flying', dislodge some quids out of your wallet and go fly a Maul!
Does anyone criticise F16 or current FBW fighter pilot as being a lesser pilot than an F4 or A4 pilot?
Strange logics (no pun intended).
You are there to fly/operate a flying machine that 'makes money' for 'shareholders'. If you're lucky you have an aeroplane that makes doing that day in, day out easier and 'backs you up'.
If you wanna go 'flying', dislodge some quids out of your wallet and go fly a Maul!
Having flown both, I'd say “not at all”. Each has their challenges. But please do note that somewhere in the first few pages of the Airbus FCTM is the helpful advice that, when in direct law, one simply flies the aircraft like a conventional jet transport.
What do you expect that pro tip might mean to somone who has never done that?
i never really loved the manual flying on FBW, but then again I never HAD to, it was always done for skill retention only.
What do you expect that pro tip might mean to somone who has never done that?
i never really loved the manual flying on FBW, but then again I never HAD to, it was always done for skill retention only.
Is the C of G issue because of too much of a forward or an aft trim, or both scenarios?
If so, this maybe the case of a full Business class load in the front (and maybe cargo), and too few Y pax down the back, or vice versa...
Hardly anyone has checked bags anymore in Business so one cannot offset out of trim situations with the hold baggage.
We had a particular problem with Transavia Holland on a 737-200 used for the LGW-AMS scheduled services, which had a movable business cabin so you never knew much in advance of the variable loads - It was a pig to trim which for a 737-200 was unusual, but caused by a lot of extra metal installed in the front area due to some re-skinning (post Aloha HNL)
If so, this maybe the case of a full Business class load in the front (and maybe cargo), and too few Y pax down the back, or vice versa...
Hardly anyone has checked bags anymore in Business so one cannot offset out of trim situations with the hold baggage.
We had a particular problem with Transavia Holland on a 737-200 used for the LGW-AMS scheduled services, which had a movable business cabin so you never knew much in advance of the variable loads - It was a pig to trim which for a 737-200 was unusual, but caused by a lot of extra metal installed in the front area due to some re-skinning (post Aloha HNL)
...............how come Airbus gets away with this exemption just because the stick is on the side, while Boeing are required to create perfectly progressive stick feedback force, all the way to the extremes of the envelope, and in trying to meet the requirement, create MCAS? Progressive pitch force is a major design headache, from single engine homebuilts, right through to airliners..........
An analogy might be modern cars having ABS braking systems. Cars without ABS require the driver to prevent locking the wheels in slippery conditions, ABS performs the anti-locking function ‘in the background’. Cars with ABS are safer in slippery conditions than those without.
(ABS also works on individual locked wheels. The driver of a non ABS car can only release or apply brakes to all the wheels simultaneously).
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The Lufthansa A320neo is tail heavy because they moved the lavs into the tail using the spaceflex option and did some modifications in the front to squeeze in two extra rows of seats. The tail heavy situation was known and because of it they didn't fit the inflight WiFi equipment either.
i never really loved the manual flying on FBW, but then again I never HAD to, it was always done for skill retention only.
Any new type is going to have teething problems, the airlines always finish off the testing program for the manufactures by which stage anything major should have been picked up. It would be uneconomic and probably impossible to have a new aircraft absolutely perfect before the first delivery, some faults will only manifest themselves under very specific conditions or after a certain length of time in service.
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Lufthansa blocking off last row
This according to Aviation Week. Begs the question. If you removed the last row and re-configured the seat map so the ac would have one less row total but the 'new' last row would be in current position of the blocked row, would the CoG issue still remain?
Either way, you still have 6 sellable seats less than you started with, plus you'd have the cost of re-aligning all the PSUs, etc with the revised configuration.
Only half a speed-brake
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Therefore, if there were no extra seats, the aircraft would have requisite stability?
