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Does the 49G+ belong in this **MUSEUM**
Message #1 Posted by GE (France) on 25 Oct 2003, 5:40 p.m.

Not to be rude, but this stuff is boring.

Please bring back old stuff, collector tricks, rebuilding tips. And please please no bragging (example : "Wow, my new 4Go SD card !!"). Endless flags settings discussions not welcome either.

      
Re: Does the 49G+ belong in this **MUSEUM**
Message #2 Posted by CalcKidd on 25 Oct 2003, 9:51 p.m.,
in response to message #1 by GE (France)

We're just talking about HP calcs... OLD and NEW.

Don't limit yourself (or us).

      
Re: Does the 49G+ belong in this **MUSEUM**
Message #3 Posted by Namir Shammas on 25 Oct 2003, 10:56 p.m.,
in response to message #1 by GE (France)

GE,

This is a free country! I assume France si too .. or have the Germans invaded again???

      
Re: Does the 49G+ belong in this **MUSEUM**
Message #4 Posted by Wayne Brown on 26 Oct 2003, 1:56 a.m.,
in response to message #1 by GE (France)

I agree that discussing new calculators here is inappropriate (although I've been guilty of it myself lately). However, the Museum belongs to Dave Hicks, and if Dave doesn't mind allowing these discussions (distasteful though they might be to you and me), then I don't think we should complain about them.

      
Re: Does the 49G+ belong in this **MUSEUM**
Message #5 Posted by Massimo Gnerucci (Italy) on 26 Oct 2003, 4:23 a.m.,
in response to message #1 by GE (France)

And, please, quit using "octects" Wow, my new 4Go SD card !!: the rest of the world uses bytes.

;-)

Massimo

            
You can't win that one GE
Message #6 Posted by Norm on 27 Oct 2003, 5:48 a.m.,
in response to message #5 by Massimo Gnerucci (Italy)

Hi GE, interesting viewpoint. Concisely and briefly spoken, very sharp and well-aimed point on your pen.

You want to censor newest units, but that wont work.. There are posts here right up to the latest most recent models that have NOTHING to do with red LED's. Can you believe it?

(oooo aaaaaaahhhhh oooweeee babeee RED LED's...... hubba hubbaaa!! Hey no joke I was at an exotic dancer bar the other night. Watching all those gals wearing nothing but....... I think the HP-34C is better...... I will bring it with me next time.... type on that HP-34C instead, keep my head down and bring a math book. Then they wont keep bugging me to buy a table dance).

:o| :o)

HEY GE did you see the link for HP-33S ????? It's the "newest best" calculator from HP !!! http://www.samsoncables.com/catalog/prodDetail.cfm?Prod_ID=363

GE people on our beloved chat board are eagerly waiting to buy it....... use it...... and post about it ! Its gonna be tough for you... and me! You are right though... it IS a "museum" but where do you draw the line...... so you don't!

                  
Re: You can't win that one GE
Message #7 Posted by Dave Shaffer on 27 Oct 2003, 11:22 a.m.,
in response to message #6 by Norm

Norm,

re: "Hey no joke I was at an exotic dancer bar the other night. Watching all those gals wearing nothing but....... I think the HP-34C is better...... I will bring it with me next time.... type on that HP-34C instead, keep my head down and bring a math book. Then they wont keep bugging me to buy a table dance)."

You'll be in good company: the late Richard Feynman (Caltech professor, Nobel laureate, and the guy who figured out what went wrong with the Challenger) used to hang out at the nudie bars in Pasadena, claiming he could do his best thinking there. He used to be called as a character witness when they got busted!

                        
A favorite book
Message #8 Posted by bill platt on 27 Oct 2003, 11:43 a.m.,
in response to message #7 by Dave Shaffer

Title: Surely You're Joking, Mr. Feynman

Feynman could:

out-do an abacus in his head

make french fries,

get lucky with numbers,

crack safes,

get laid by barflies, (eventually)

watch nuclear detonations without going blind

play drums in the Carnival (yes, in Brazil)

motivate ordinary persons to achieve amazing intellectual feats

get lucky with numbers

speak his mind

Paint nudes

do it (oops, said that already)

upset the textbook publishing business

speak his mind

Explain strange physics better than anyone (see "QED: the Strange Theory of Light and Matter, and also the Feynman Lectures)

get lucky with numbers

Amazing person.

                              
Re: A favorite book
Message #9 Posted by GE (France) on 28 Oct 2003, 8:35 p.m.,
in response to message #8 by bill platt

Well done boys. I knew you would understand the basic, primal feel for RED-LEDs. Thank you for no name caling, and the joy of meeting people deeply conscious of the greatness of lower, shameful low-end, disgusting low-power things like the onboard Apollo 11 computer, HP35, HP9825, and many others, who are such a pile of crap for not having a 3 Ghz CPU and just being able to send people to the moon as compared to making big bucks at your local Wal-Mart. Sorry for giving a shit to REAL engineers and not just $$$-lionaires ! I Should respect $$$$ instead of proper design. Won't make this mistake twice. Also, I'll set flag 456 in order to speed up some remote calculation case as discussed for 3 weeks in this very forum *devoted* to *OLD* (read : 2-week old) calculators.

Apart from that, thanks to all serious (old calculators) on this forum.

                                    
GE you forgot to mention
Message #10 Posted by Norm on 29 Oct 2003, 4:23 a.m.,
in response to message #9 by GE (France)

Hi GE, you forgot to mention that your favorite 1960's Apollo launch computer.... or HP calculator, etc., has a CPU that RUNS RELIABLY however that 3GHz baby from Bill Gates hangs about every 3rd day (probably when the 64 bit bus changes from all 1's to all 0's enough times to make the backplane resonate) and nobody knows why, and who cares, if it only crashes every 3rd day, its reliable.... right ?????

(you can always reboot it...... wanna know a scary fact about the 777 first test flight ever???? So the computer has some bug in it and the software guys never fixed it. The airplane is sitting on the numbers and they want to fly it, the engines are idling...... and it just sits there.

After a couple minute delay, the pilots take off in the 777 first ever prototype maiden test flight. The reason for the delay????? The software bug makes the avionics computer malfunction, so the pilots had to go running down into the avionics bay underneath the cockpit........ and pull the main breaker to "off"...... and then "ON" again !!!!!!

Wish I were joking, but I'm not.... who can understand the minds of the software-heads..........the manager-heads....... the anti-RPN crowd...... or inside the brain of Carly Fiorina. They better hope that nobody needs to reboot their 777 computer while they are on-final on a dark foggy night, but of course, if it works 2 days out of 3, that's OK in the Starbucks/Bill Gates society, right ?

                                          
Scary 777
Message #11 Posted by bill platt (les Estats Unis d'Amerique) on 29 Oct 2003, 9:38 a.m.,
in response to message #10 by Norm

Hi Norm,

Can you find us some substantiation for this?!!! It is scary.

                                                
Re: Scary 777
Message #12 Posted by Norm on 29 Oct 2003, 2:52 p.m.,
in response to message #11 by bill platt (les Estats Unis d'Amerique)

Read it in some book, of course, about the 777 project.

No, didn't make it up out of thin air.

I think it was "21st Century Jet". If you want me to verify any further let me know, I got a copy around here somewhere.

Of course by now they have fixed the software bug.

What's interesting is they flew on that day by turning the computer off and on....... right out on the runway. That's a Bill Gates mentality, of accomodating unreliable equipment.

ABOUT THE FOLLOWING POST (airbus not immune, etc.) That article talks about whether pilots are allowed to make extreme maneuvers. With the Airbusted, they are not allowed, with the Boeing, they are allowed.

Perhaps the philosophy should be called into question now that Mohammed Atta types could be your co-pilot. It might help a little if the plane restricted its own movements, say when Co-pilot Batooti crashed the Egyptian Air 767 into the ocean (what a guy).

                                          
Airbus is not immune . . .
Message #13 Posted by Paul Brogger on 29 Oct 2003, 10:10 a.m.,
in response to message #10 by Norm

See the last part of this article about fly-by-wire . . .

                                                
Re: Airbus is not immune . . .
Message #14 Posted by jimc on 29 Oct 2003, 4:52 p.m.,
in response to message #13 by Paul Brogger

My Chev truck wouldn't start one afternoon out in the field. Just wouldn't. Nothing. No radio, no windows, nuthin'. As I, trying to be the good engineer sat there futilely trying to trace "OK, gas, spark, air", (Ever look under the hood of one of these things?) one of the operators in the field comes by and pulls the positive terminal off the battery, waits 30 seconds and bolts it down again. Truck starts! "What the heck was that?" I ask, and the operator responds "Dunno. It's like you gotta reboot the computer".

not sure about the exact cause, all I know is it worked.

12345

                                                      
more over-computerization
Message #15 Posted by db(martinez,california) on 29 Oct 2003, 9:12 p.m.,
in response to message #14 by jimc

If the latest model of the Caterpillar 627 scraper (i think it's the 627H) stops or quits running the first thing to check is the fuse for the cigarette lighter. I don't know why but a dead lighter tells the computer that the motor should not run. Maybe the designer is a smoker.

                                                      
Re: Chevy truck
Message #16 Posted by Norm on 30 Oct 2003, 1:36 a.m.,
in response to message #14 by jimc

Holy cow, that's one to keep in mind. Gotta reboot the car's engine computer to make it start.

My Chevy truck has got too much computer flim-flam on it (Bill Gates mentality). Like, I dont have control over my dome light. It turns it out automatically about 60 seconds after I leave the car. I dont like that. It's my business, not theirs. I don't have control over the headlights. They come on when I put it in "Drive". I dont like that none of their business.

So I'm out in Wyoming going like a bat out of hell, and when I hit right about 99 - 101 miles an hour, the engine ceases firing, until the speed comes down to about 95. Apparently the engine computer has a hard-limit at 100 miles an hour, and if you hit the limit, it shuts off the fuel injectors.

I say that's none of their damn business how fast I am going, and they ought not to limit my max speed. Ever seen the videotape of some guys trying to outrun a tornado on the freeway? It's like, right behind 'em!! If you were in the Chevy you'd be dead.

I'm with Boeing not Airbus. "If its not Boeing I'm not going"

(well OK, I went, but only with a guilt complex).

                                                            
Re: Chevy truck
Message #17 Posted by Wayne Brown on 30 Oct 2003, 1:38 p.m.,
in response to message #16 by Norm

Quote:
Holy cow, that's one to keep in mind. Gotta reboot the car's engine computer to make it start.
I had to have the engine computer in my car replaced about a couple of weeks ago. This is what happened: I drove it to work one morning -- everything was fine. I went to lunch that day -- still fine. I tried to drive home that night -- it wouldn't start. Well, actually, it did start, but immediately stopped again aftr runing two or three seconds. This happened every time I tried to start it. I played around with it off and on for a few days, and verified that it was getting plenty of gas, the wiring and fuses seemed fine, the built-in engine diagnostic codes said there was nothing wrong, etc. I also had a shade-tree mechanic friend take a look at it. Finally my wife got tired of driving me to work so I just had it towed to a garage. They discovered that the engine computer had decided that the anti-theft system was reporting the car was being stolen, so it shut down the engine every time it was started. The cute thing was that my car doesn't have an anti-theft system! The computer apparently was programmed to handle one if it was installed, and it went bonkers and decided the non-existent system had been activated. There was no way to reset it, so a new computer had to be installed. Parts, labor and towing came to a little over $500. Grrrrrrr...
                                                            
Saab 900 long
Message #18 Posted by bill platt on 30 Oct 2003, 3:47 p.m.,
in response to message #16 by Norm

I had an '87 saab, great car, ran nicely, reliable, etc. Mechanical fuel injection. Replaced it with an '85 saab 4 door--another nice car. Year later, that gets totalled by an undocumented driver. When I asked to see his papers, he drove away!

So, Got a 1990 saab, thinking, these are cool cars, they are very safe, pretty good on gas, very comfortable, low cost (for a eurocar anyway).

Well, the 90 was a whole nother ballgame. ECU or ECM or something. That godddaaammm thing was nothing but trouble. Finally got tired of repacing it--3 times--and now that car sits in the yard, serving as a Property Value Reduction Prop. Next week, I plan on taking the wheels off, sitting the car on blocks----since the house across the street just sold for 375k ;^}

Apparently, they went "electronic" in 89 or 90 or something.

Also, Detroit diesel is involved in a massive lawsuit from a major shipowner, regarding their electronically controlled high speed 4 cycle diesels. Apparently, they are not making the 15k hours between rebuild--more like 500 to 1000!

And, I know of some smaller ferry operators who shy away from the electronic ones--had troubles etc.

You know, electricity is great and all, but why does it seem like it is less reliable now than in the past? (I can answer that but I wont--too much of a rant).

So, why is this relevant? Because In 20 years of using an 11c and 32sii, I have NEVER had to "reboot". But how about the 49g+----see c.s.hp48 and yo uhear reports.....

Here's another curio: Big Shipyard, Big Mainframe, Unix. 150 CAD workstations--running different programs. Programs linked to eachother. Not a single crash in 7 weeks.

Another shipyard. a "Microsoft" approach. Microsoft NT server, 50 Cad workstations, local machines windows NT4 SP3. Crash server almost daily. Crash local machines more than once a day. Blue Screen of Death, and others, too.

Why do we accept this?! Why are we throwing away stable UNIX systems for this CRAP! So we can have eXcel or Word?! For C...sakes..those programs arent't THAT good....(I liked Word Perfect 5.2 more--and Quattro Pro had more functionality...)

So, along that line, I am NOT going to buy a 49G+ for a while---I don't want to encourage them! Send the useless junk marketeers the only message they understand---nothing!

                                                                  
Re: Saab 900 long
Message #19 Posted by Dave Shaffer on 30 Oct 2003, 5:50 p.m.,
in response to message #18 by bill platt

"I liked Word Perfect 5.2 more"

Hear! Hear!

Best word processor program ever made. Especially if you want a macro that replaces/changes system formatting codes. You can't do stuff now (WPWin 8, 10, 11) that you could half a dozen versions ago (but you can still do WAY more of that than you can with Word).

                                                                        
@&%$! MSWord
Message #20 Posted by james (UK) on 30 Oct 2003, 6:35 p.m.,
in response to message #19 by Dave Shaffer

Don't get me started on %&^&*&"@ Word! Everytime you try and type something the damn program thinks it knows better than you how to format what you're trying to do - oops showing me age again - for 'type' read 'word-process' - aaargh - going off to bathe in the soothing red glow of some leds to calm down!!!

                                                                  
Saab 900 dont put it on cinder blocks
Message #21 Posted by Norm on 31 Oct 2003, 4:54 a.m.,
in response to message #18 by bill platt

Bill Platt wrote:

>> That godddaaammm thing was nothing but trouble. Finally got tired of repacing it--3 times--and now that car sits in the yard, serving as a Property Value Reduction Prop. Next week, I plan on taking the wheels off, sitting the car on blocks----since the house across the street just sold for 375k ;^}

*** HEY BILL after you take the wheels off don't leave it on cinder blocks, cinder blocks cost money.

Just turn it upside down.

                                                            
Chevy truck
Message #22 Posted by james (UK) on 30 Oct 2003, 6:37 p.m.,
in response to message #16 by Norm

This truck has performed an illegal operation and will now shut down. (Cue hourglass symbol)

                                                            
Simpler times (O/T)
Message #23 Posted by james(UK) on 31 Oct 2003, 8:57 a.m.,
in response to message #16 by Norm

Re too much thought control in today's autos, an extract from an article by Paul Cockburn on the E-Type Jaguar (XKE) in the Australian car mag 'Wheels'

"I read somewhere recently where the current Cadillac has 103 separate electric motors aboard to make your life that little bit easier.

That's nice.

The Series 1 E-Type has three that usually do something. Starter motor, fuel pump and radiator fan.

It has another two that work, but do nothing worth a damn (the heater fan and windscreen wipers) and one that does something very peculiar (the screen washer switch, when activated, soaks the passenger's right foot).

The only other one that I know of drives (for a few moments after delivery and any subsequent attempts at repair) the rightly famed Sir William Lyons Memorial Clock, which sits in the rev-counter of every early E-Type and almost immediately seizes at 25 to 12 .... presumably predicting the moment of his departure from the mortal coil.

It has pwoer-operated nothing.

You want the windows up? Sort them out yourself.

Think of erecting the roof as a mental and physical accomplishment.

Steer it like a man, damn you!

God will determine the condition of the air. And so on."

                                                
Re: Airbus is not immune . . .
Message #24 Posted by Vassilis Prevelakis on 31 Oct 2003, 7:29 p.m.,
in response to message #13 by Paul Brogger

a) Unreliable software is not a "new" thing. There were bugs even in early HP calculators, despite the fact that the code was much smaller and the product develpoment cycles were longer.

b) The first flight of Columbia had to be postponed for 2 days because of a software bug. The four PASS computers (primary avionics) could not sync with the backup flight computer. Somebody suggested rebooting everything. NASA did not want to try this especially with Columbia fully fueled and ready to go. So they cancelled the launch and tried again the following Monday. The second time everything went OK. Over the weekend they found and bypassed the bug, which had 1 chance in 64 of occuring (so if they had rebooted, chances were that the computers would sync).

c) Having computers ensure that the plane stays within a safe envelope will not make the plane safe. The recent crash of the AA Airbus 320 over NY (where the pilot commanded a series of end-to-end deflections of the rudder, causing the vertical stabilizer to break off) proves that the "user" can always cause unpredicted behavior.

d) In the case of the 747 that went out of control, it may be worth investigating whether envelope protection would have prevented the incident from occuring in the first place. Also in another incident (in the Philipines) the pilots could not regain control of the plane (another 747) and it crashed.

e) The traditional way of controling flight surfaces is dead, because it costs too much (weight, manufacturing, maintenance, etc.). Even in traditional flight control systems a degree of automation exists. E.g. in large planes such as the 747, MD11, etc, you need hydraulic pressure to control the flight surfaces anyway. So the pilot's controls are not linked directly to the flight surfaces. In these cases feedback to the pilot (e.g. the stick shacking when the plane approaches stall) are "simulated" (e.g. by having a motor shake the stick when the plane approaches stall). In the O Hare DC 10 crash (where one of the engines detached from the wing taking with it all three hydraulic lines) the pilots stick shaker did not work because it was powered from an electrical power bus that was powered from the missing engine. (so what about the co-pilots stick shaker? it was an optional extra and was not installed). The plane stalled and crashed.

f) (to finish on a possitive note) Having a fully manual backup can save your ass. Remember the Air Canada 767 that run out of fuel. The pilots managed to land it on an unused strip by gliding. Most of the avionics were dead (they had a little bit of power from a windmill generator), even the APU was dead since it uses fuel from the main tanks. Of course the hydraulics had pressure, but without power the pilots could only achieve reduced deflections of the fligh surfaces (like braking your car with the engine switched off). (In fact the nose landing gear did not deploy properly because it drops against the wind stream, and the plane suffered some damage).

**vp

                                                      
Re: Airbus is not immune . . .
Message #25 Posted by Norm on 1 Nov 2003, 5:22 a.m.,
in response to message #24 by Vassilis Prevelakis

VP wrote:

>> AA Airbus 320 over NY (where the pilot commanded a series of end-to-end deflections of the rudder, causing the vertical stabilizer to break off)

Hi VP, although I personally don't believe in vertical stabilizers they break off (an Airbus innovation) do you know anything further about why the pilot pressed end-to-end? Are you sure the command was so extreme?

VP wrote:

>> In the case of the 747 that went out of control, it may be worth investigating whether envelope protection would have prevented the incident

Hi VP, it would have, in this situation. The reason the 747 begins with that they were flying very high (maybe 37,000 feet or whatever is higher than usual) . Then the initiating problem was that one of the 4 engines quit. It was a flameout, or some such minor thing. However, when in the very rarified atmosphere, you must maintain airspeed. If an engine quits, you must lower the nose (descend) and probably lower the nose quite strongly. The pilot did not significantly lower the nose. As a result, the airplane on 3 engines quickly went into a stall, probably on one wing first. This made it tumble crazily and caused a lot of upside-down gravity etc. from which they were lucky to recover. Therefore to answer your question the AIRBUSTED philosophy of intervening over the pilot WOULD HAVE prevented the incident (the airplane would've shoved the nose down harder than the pilot did).

I dont know if the Airbus philosophy is better however. The computer guys write buggy code and they may cause more accidents than they prevent.

VP wrote:

>>> In the O Hare DC 10 crash (where one of the engines detached from the wing taking with it all three hydraulic lines) the pilots stick shaker did not work because it was powered from an electrical power bus that was powered from the missing engine. (so what about the co-pilots stick shaker? it was an optional extra and was not installed). The plane stalled and crashed.

Keep in mind that there were other disasters at work. The DC-10 like most big jets has got leading-edge flap surfaces and trailing edge flap surfaces. They have to extend together; if one extends and the other doesn't you have a junk airfoil that won't fly. The leading edge flaps were held in position by hydraulic fluid only, even though it was tradition to use mechanical locks also, the managers decided on a payraise t(o executives only) instead and used hydraulic fluid only for locking the leading edge flaps. When the engine came loose (due to uncertified maintenance procedures damaging the engine mount) it ripped loose all the hydraulic lines like a bunch of spaghetti. The hydraulic pressure failed on one side only and the leading edge flaps retracted on the one side while the big trailing edge flaps were still extended. The pilot now had a junk airfoil. Sadly it was still flying as he was climbing out, however the book called for him to REDUCE his airspeed as part of a failed engine. He didn't know that he had even lost an engine; when the airspeed was reduced the improperly configured wing stalled unexpectedly (left side) and the plane rolled to the left, flipped over and hit the ground.

Therefore a variety of problems there; bad hydraulic designs, management cheapout, and regulations on the pilot that didn't prove advantageous (if I was flying and I lose an engine I'd want to go like hell, keep my airspeed up).

- Norm

                                                            
Re: Airbus is not immune . . .
Message #26 Posted by james (UK) on 1 Nov 2003, 6:21 a.m.,
in response to message #25 by Norm

From what I remember, the Airbus was turning and following a plane in front (also turning) and twice ran into that planes wake turbulence, the first time the pilot managed to regain control through reversing the rudder a couple of times, unfortunately the second time structural failure intervened.

According to Airbus, it was a mixture of pilot error (shouldn't have reversed the rudder as this imposes way too much stress) and the airline (their manuals didn't tell the pilot what he should do). Apparently simulations have shown very high stresses in these situations but funny how pilots have been reversing the rudder on Boeings and other planes since the days of Orville & Wilbur without any problem.

                                                                  
Kind of like don't push the throttle lever too far forward
Message #27 Posted by Norm on 2 Nov 2003, 3:47 a.m.,
in response to message #26 by james (UK)

Kind of like if it said "don't push the throttle lever too far forward....."

"if you do, the knob falls off in your hands."

The owner's manual says thats what will happen, so its OK that it is what happens.

"dont push rudder pedal too hard, rudder might fall off".

Interesting how all the blue-suits and the lawyers and the managers are willing to keep a straight face while they say such lunacies. I suppose they can't just admit the truth (rudder was too flimsy, shouldn't fall off) because then the lawsuits will win bigger.

                                                            
Re: Airbus is not immune . . .
Message #28 Posted by Vassilis Prevelakis on 2 Nov 2003, 12:11 a.m.,
in response to message #25 by Norm

Norm wrote:
> Hi VP, although I personally don't believe in vertical
> stabilizers they break off (an Airbus innovation) [...]

rather harsh statement, read below:

From Aviation Week and Space Technology, Nov 25, 2002 > The Airbus A300-600R's rudder moved from stop to stop five > times, causing the vertical stabilizer to be torn from the > transport. The total force exerted was 1.93 times limit > load, the maximum load expected in service.

From Aviation Week and Space Technology, Feb 8, 2002: > NTSB officials stressed that problems from successive > rudder inputs is a threat on all transport aircraft, not > just Airbus A300-600s.

In fact the KC-135 (military version of the the Boing 707) manual specifically cautions against rudder reversals.

My point was not to say my plane is better than your plane (unlike John Travolta, I don't actually own an airliner :-). My point was that this was one case where envelope protection may have prevented the accident.

> I dont know if the Airbus philosophy is better however.
Neither do I. This is why I gave examples both for and
against. The court is still out.

> The computer guys write buggy code and they may cause > more accidents than they prevent.

This statement is so general as to be useless. Computers are used in both Boing and Airbus airliners and soon they will be used in practically all aircraft.

In reality, technology and economics force the replacement of manually driven actuators with computer driven ones.

You have to realize that old technology is not inherently better because its does not involve computers. Its just different. It has its own problems, like things falling off without the pilot having a clue (O Hare crash), like elevators being incorrectly adjusted (TWO recent USAir Express crashes), etc.

(regarding the DC-10 O Hare crash)
> Keep in mind that there were other disasters at work. 

Of course. Most accidents are due to an unfortunate conbination of events. The DC-10 crash was one of these cases. However, my point was not that the stick shaker was the root cause of that crash, but that even in older aircraft that do not use "fly-by-wire" technology, there is still a lot of automation that can ruin your day.

                                                                  
Hmmmmmmmm Work for Airbus ?
Message #29 Posted by Norm on 2 Nov 2003, 3:51 a.m.,
in response to message #28 by Vassilis Prevelakis

Hmmmmmmmmm. Sounds like you work for Airbus.... in the legal department.

Well, if I understand your position correctly, Vassilis, you are saying that its mechanically OK to put a rudder on the airplane that will fall off with stop-to-stop actuation. (I guess they do that by using plastic bolts and chewing gum, etc.)

So you are telling me its OK to make a rudder like that, so long as the software is coded to prevent the pilot from stomping on the rudder pedals. Ok...... whatever you say.

You done much flying ? Take any lessons ?

                                                                        
Re: Airbus is not immune . . .
Message #30 Posted by Vassilis Prevelakis on 2 Nov 2003, 5:23 a.m.,
in response to message #29 by Norm

> Well, if I understand your position correctly, Vassilis,
> you are saying that its mechanically OK to put a rudder on
> the airplane that will fall off with stop-to-stop
> actuation. 

Which part of "The Airbus A300-600R's rudder moved from stop to stop five times" you don't understand? In an earlier flight (AA 903) the rudder was moved end-to-end eight times and did not fall off, because it is contructed of composite materials and has been overengineered on purpose.

--------------------

Regarding my previous posting:

a) I quoted the NTSB statement from AW&ST. If you think you know more than these guys then apply for a job at NTSB and save thousands of lives.

b) Planes, unlike Abrams M1 tanks are by design fragile. They are not made of steel or titanium, but aluminum and composites. This is because the higher the dry mass of an airplane the less payload (i.e. paying pax or cargo) you can carry for a given MTOW (max take-off weight). So, guess what, if you apply the thrust reversers in flight, the plane falls to bits. If you do this in an M1 you make a big hole in the ground and you simply have to back out. The flight instruction manual tells you what you can and what you cannot do. Pilots have to obey these rules. The more professional the pilot the closer he or she follows the book. Sometimes the book is wrong (like in the case of the O Hare crash) and people get killed. In most cases the book is right and everybody gets to tell scary stories to their grandchildren.

c) Screwing around with a two story rudder will get you in trouble. The big question during the inquiry was whether this needed to be stressed in the aircraft manual and the AAMP (Advanced Aircraft Maneuvering Program), or that this should be self evident. The KC-135 manual includes this warning. NTSB board member J.A. Hammerschmidt and some American Airlines pilots were receiving the impression that the AAMP indicated that rudder, rather than ailerons was the primary method for roll control in some upset circumstances including wake encounters (AW&ST Nov 4, p.47). One of the recommendation of the board was that this had to clarified.

d) Ultimate load for the vertical stabilizer is 1.5 limit load (maximum load expected in service). In the case of flight 587, the tail broke off when the actual load reached 1.93 of limit load. The A300-600 tail is actually 30% stronger than required, which allowed other flights (e.g. AA 903 where during 8 rudder reversals the ultimate load was exceeded 3 times) to survive.

e) There are lots of things you shouldn't do when flying an airplane (e.g. applying the thrust reversers, lowering the landing gear at cruising speed, etc.). For some of these things there are safeguards that prevent the pilot from performing the action, for others, the pilot can perform the action and pray that he/she can get away with it. In the two cases mentioned above (thrust reversers, and landing gear) there are mechanical interlocks that prevent accidental deployment. As computers are gradually installed between the pilot and the plane, some/most/all of these interlocks will be implemented in software. While I am not sure whether its a wise decision, I predict that most new planes that will be built in the next ten years (Boeing 7E7, Airbus 380-800, etc) will have software that will be flying the plane and the pilot will be less in control.

----------------------

> Sounds like you work for Airbus....
The question should be whether I work for the aircraft industry. :-) Airbus, Boeing, Bombardier, everyone has to make products that are sellable, i.e. economical to purchase, operate, maintain, and so on. They all have to make design decisions on how to reduce weight, automate tasks (e.g. this is how they got rid of the flight engineer), simplify maintenance and (of course) operate within the parameters specified by national and international law. So everybody is trying to get as close to the sweet spot by coming up with new solutions. In some cases they are rewarded because these solutions allow them to improve their price/performance, in other cases they have to backtrack and pay millions of dollars to remove the "optimization".

Feel free to question what I say, but before you respond, check the NTSB report, and the AW&ST website (www.aviationnow.com).

Now can we get back to HP calculators?

**vp

                                                                              
Re: Airbus is not immune . . .
Message #31 Posted by Norm on 2 Nov 2003, 2:37 p.m.,
in response to message #30 by Vassilis Prevelakis

VP wrote: Now can we get back to HP calculators? **vp

No, we can't. Your viewpoint is terrifying, I wish to make sure I really understand it.

As an analog electronics engineer, I have watched the software types slowly come to power and tighten their stranglehold on society with their viewpoint that 'things ought not to work properly'.

I am familiar with the design of linear amplifiers. It can be difficult to make the linear amplifier stable under some conditions, so it oscillates. Thus comes the heart & soul of analog electronics, to make things work properly. BUT NOW comes the software guys.... and my impression of them (as far back as 20 yrs ago) was that they would just assume have an UNSTABLE badly performing amplifier (like for their stereo speakers) just so long as they get to add a microprocessor and some lines of code, imagining in their childlike fantasies that they get to sort of 'clean up' what they dont understand by tap-tap-tapping at their little keyboards and running their tidbits of assembler instructions.

Well, I dont buy it. I think you software guys would just assume put in a substandard foundation underneath a 50 story building..... like not use very much cement so maybe it wants to tip over. After all, we can just add a microprocessor and just write a few lines of code!!!!!

You seem to have some expertise about the crash of the Airbus jet. So, did anybody change ANYTHING in the design? Or did they just count the number of stop-to-stops of the pilots feet and say '5 is too many'.

In advance, it sounds like they did not do ANYTHING!!! This conveys a total disrespect for people's lives, comparable to Ford/Firestone.

I think software people are unwilling to look at the big picture. You say 'the rudder is 2 stories, of course it falls off'. You keep pointing out that it was at 1.93 of the supposed 'load limit'. Did it ever occur to you that maybe the load limit number is WRONG? Maybe it failed at 0.5 of the fair load limit, if you only pick a reasonable design limit in thei first place.

WELL how about designing the rudder extra strong at the bottom, with a deliberate breakpoint up higher so that if the worst-case nightmare occurs, the pilot can still fly home on half a rudder? Why? Because of the middle managers! This would require them to actually think, and maybe have a bunch of fresh work to do, and maybe they don't want to do that. So they shall just do nothing!!! Did you know that the Concorde crash was preceded by NUMEROUS examples of the exact same problem, but the managers did nothing? Did you know in the 70's that TWO DC-10's were damaged or lost due to cargo-door failure, before the middle managers finally got kicked off their butts and onto their feets to actually do something about it?

Back to software, you keep assuming that the jet flies in a straight line, so that the rudder doesn't have to do very much. Well, how about if the plane tumbles in flight. How about if there is a screwup and it flies into a cumulus cloud. How about if your co-pilot is an arab like Bhatouti. You could wind up damn near crossways to the wind stream under any of these conditions. The China airlines (?) 747 certainly did when it tumbled from 37,000 feet after a turbine trip.

I have to presume you are just toying with my mind and that is why you write this stuff, so if you dont want to reply fine.

As to me, I absolutely do not believe in rudders that snap off due to a pilot stomping on rudder pedals, and perhaps you should reiterate your viewpoints to the victim's families.

- Norm

                                                                                    
Re: Airbus is not immune . . .
Message #32 Posted by Vassilis Prevelakis on 2 Nov 2003, 4:10 p.m.,
in response to message #31 by Norm

Norm wrote:
> You seem to have some expertise about the crash of the
> Airbus jet. So, did anybody change ANYTHING in the design?
> Or did they just count the number of stop-to-stops of the
> pilots feet and say '5 is too many'.
>
> In advance, it sounds like they did not do ANYTHING!!! 

Go read the NTSB report (and recommendations) on the accident, its on the web.

**vp

                                                                                          
Re: Airbus is not immune . . .
Message #33 Posted by Norm on 3 Nov 2003, 12:50 a.m.,
in response to message #32 by Vassilis Prevelakis

Well, Vassilis, cooperative teamwork is about if you know something, you are welcome to fill me in. I dont have time to go and read this report, and if you have already done so, you are welcome to provide me with details.

Meanwhile I promise next time I am in a Cessna 172 I will caefully count my applications of rudder pedal and be very careful not to exceed 5 counts lest I break off the rudder and crash. I believe that makes good sense to me.

As you do not wish to provide useful facts or details (did Airbus do anything after the crash???) and you continue to cling to the notion that "5 is too many" (or whatever the airbus lawyer said) I think I too am ready to bid farewell to this exchange.

As before, I reiterate my suggestion..... go share your viewpoints with victim's families.... starting with the wife of the captain of the Airbus. BTW the captain is obviously being blamed after his death as a scapegoat, a common tactic by businessmen and MBA's who care less about technical realities. Too bad you are on their side.

- Norm

                                                                                                
Re: Airbus is not immune . . .
Message #34 Posted by Dirty Harry on 3 Nov 2003, 4:23 a.m.,
in response to message #33 by Norm

" I know what you are thinking...
did i push the rudder pedals six times or was it only four?

To tell you the truth I've forgot it myself
in all this excitement.

Now this is an Airbus A330, the most
powerful airplane in the world, but it
can blow its tailfin clear off.
Now you must ask yourself one question, pilot:
" Do you feel lucky ?"

............... Well do you... Pilot?

---Dirty Harry

                                                                                                
Re: Airbus is not immune . . .
Message #35 Posted by Vassilis Prevelakis on 3 Nov 2003, 6:39 p.m.,
in response to message #33 by Norm

Norm wrote:
> I dont have time to go and read [the NTSB] report
> and if you have already done so, you are welcome to
> provide me with details.

I see, you have the time to draw conclusions based on total speculation. E.g.

> In advance, it sounds like they did not do ANYTHING!!!
> This conveys a total disrespect for people's lives [...]

... but you do not have the time to go and read a couple of pages so that you can get a first hand idea of what the experts believe really happened.

So, OK Norm, you are absolutely right. Airbus is total trash and we must urge all people never to set foot on one of their flying coffins. Now that this has been settled, take a few deep breaths and go back to your important work that leaves you no free time.

And now that you have shown me the light, can we go back to calculators?

**vp

                                                                                                      
Vassilis,
Message #36 Posted by Norm on 3 Nov 2003, 7:16 p.m.,
in response to message #35 by Vassilis Prevelakis

Vassilis,

I really have no further need to absorb your "wisdom" that killed hundreds on that Airbus flight. I also find your helpful and cooperative spirit most intriguing, in which you refuse to describe whether any subsequent mods (presumably strengthening the flimsy rudder) were, or were not, implemented.

Actually I can clearly see why you would refuse to answer the question... you lose either way

(a) if they strengthened the tail, then the captain you are damning (for having pushed the rudder pedal 5 times) would be vindicated, since they made structural changes (b) if they did not strengthen the tail, then its just as flimsy as ever and another will crash very soon

Therefore, Vassilis, you try to "win" by becoming obsessed with the fact that I have not sat down to read some lengthy report (its true, why should I, tail-fin fell off because pilot used rudder, what more do I need to know!)

Please note that I posted with my genuine name, a genuine e-mail address. Now, shouldn't you quit pestering all the people on this chat board (including me) with your desire to make pilots count the number of times they count rudder actuations (1, 2, 3, 4, oops!) BECAUSE if you have any specific need to contact me further, you may do it direct to my e-mail,and I will continue to try to assist you to learn prudent and logical engineering practice.

BTW along with logical engineering thought processes being on my side, the victims and their families would also be on my side of this debate, something you repeatedly refuse to acknowledge (instead you are dwelling on whether I have read precisely the same scraps of paper as you, which obviously is unlikely for two chat board participants to have read the same materials in advance, yet you seem to find great satisfaction in dwelling on that detail).

Again, please send it direct, or not at all. I post here only because along with your continuing conviction that its OK for airframes to fall apart, you also do not divulge your e-mail address.

- Norm

                                          
Re: GE you forgot to mention
Message #37 Posted by Les Bell [Sydney] on 29 Oct 2003, 5:55 p.m.,
in response to message #10 by Norm

The F-22 has been suffering similar problems in its avionics suite software, to the extent of requiring a reboot several times in a typical early test flight. That's rebooting in flight, folks.

Things have improved somewhat, though - apparently they only lose a few minutes while rebooting as opposed to half an hour or so during early flights.

The original "Atlanta Journal & Constitution" article is gone now, but a Slashdot story still refers to it, at http://slashdot.org/articles/02/07/22/0615221.shtml?tid=126.

I always thought that for test pilots, the object of the game was not to cheat death, but not to let him play the game in the first place. Perhaps times have changed. . .

Best,

--- Les [http://www.lesbell.com.au]


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