• There seems to be an uptick in Political comments in recent months. Those of us who are long time members of the site know that Political and Religious content has been banned for years. Nothing has changed. Please leave all political and religious comments out of the forums.

    If you recently joined the forums you were not presented with this restriction in the terms of service. This was due to a conversion error when we went from vBulletin to Xenforo. We have updated our terms of service to reflect these corrections.

    Please note any post refering to a politician will be considered political even if it is intended to be humor. Our experience is these topics have a way of dividing the forums and causing deep resentment among members. It is a poison to the community. We appreciate compliance with the rules.

    The Staff of SOH

  • Server side Maintenance is done. We still have an update to the forum software to run but that one will have to wait for a better time.

i choose "not"

cheezyflier

Charter Member
i read yahoo certain comics every morning with breakfast. in this case i do not believe item #1, and for item #3, well, that's a little creepy

largeimage.a5daa84bd0fe7e0bf8ed1c60b59f0319.gif
 
If by complex, they mean more lines of code... yes I can believe it. It's the old cheaper, faster, better problem. Pick one or two and if moves you away from the remaining factors.

In the case of the raptor, they can pick faster and better since they have gobs of money and time (compared to the life cycle of a car). In the case of the car, I'm sure they went with at least cheaper. Less time, less money, less optimized and bigger code.

I too have hard time believing that the car's computer have "more to do" though.
 
the reason i have trouble believing it is because aside from the radar and navigational stuff, there are the weapons systems, the parts of the computer that handle contol surfaces, interpret guage readings, handle thrust vectoring, produce stall warnings, etc. i don't know if there is such a thing, but if the computer handles any part of the stealth capability, like anti-radar or jamming then that would be yet another thing
 
Airborne Computers

The statement is based in fact. Most of the computers on aircraft are a couple of generations behind, as the system has to be ULTRA reliable and able to withstand extreme conditions. The timelag to test and retest lines of code and technology to stabilize hardware designs/software is substantial. I don't imagine the lag is as great in the auto industry.

Regards, Rob:ernae:
 
The statement is based in fact. Most of the computers on aircraft are a couple of generations behind, as the system has to be ULTRA reliable and able to withstand extreme conditions. The timelag to test and retest lines of code and technology to stabilize hardware designs/software is substantial. I don't imagine the lag is as great in the auto industry.

Regards, Rob:ernae:

Ditto; the same is even true with the Space Shuttle.

Here is an article online about the change process that is gone through to make changes to the code used in the Space Shuttle's computers. It is an exhaustive and slow process of testing, committee approvals, and extensive documentation of each change; not the midnight coke-and-pizza code crunch sessions used by many organizations to make changes to their computer code.

http://www.fastcompany.com/magazine/06/writestuff.html

For those who are interested in these things; here is Wikipedia's writeup on the Space Shuttle's flight systems:

Early shuttle missions took along the GRiD Compass, arguably one of the first laptop computers. The Compass sold poorly, as it cost at least US$8000, but it offered unmatched performance for its weight and size.<SUP class=reference id=cite_ref-GRiD_22-0>[23]</SUP> NASA was one of its main customers.<SUP class=reference id=cite_ref-GRiDNASA_23-0>[24]</SUP>

The shuttle was one of the earliest craft to use a computerized fly-by-wire digital flight control system. This means no mechanical or hydraulic linkages connect the pilot's control stick to the control surfaces or reaction control system thrusters.

A primary concern with digital fly-by-wire systems is reliability. Much research went into the shuttle computer system. The shuttle uses five identical redundant IBM 32-bit general purpose computers (GPCs), model AP-101, constituting a type of embedded system. Four computers run specialized software called the Primary Avionics Software System (PASS). A fifth backup computer runs separate software called the Backup Flight System (BFS). Collectively they are called the Data Processing System (DPS).<SUP class=reference id=cite_ref-LogicD_24-0>[25]</SUP><SUP class=reference id=cite_ref-ibm_25-0>[26]</SUP>
<SUP></SUP>
The design goal of the shuttle's DPS is fail-operational/fail-safe reliability. After a single failure, the shuttle can still continue the mission. After two failures, it can still land safely.

The four general-purpose computers operate essentially in lockstep, checking each other. If one computer fails, the three functioning computers "vote" it out of the system. This isolates it from vehicle control. If a second computer of the three remaining fails, the two functioning computers vote it out. In the rare case of two out of four computers simultaneously failing (a two-two split), one group is picked at random.

The Backup Flight System (BFS) is separately developed software running on the fifth computer, used only if the entire four-computer primary system fails. The BFS was created because although the four primary computers are hardware redundant, they all run the same software, so a generic software problem could crash all of them. Embedded system avionic software is developed under totally different conditions from public commercial software: the number of code lines is tiny compared to a public commercial software, changes are only made infrequently and with extensive testing, and many programming and test personnel work on the small amount of computer code. However, in theory it can still fail, and the BFS exists for that contingency. While BFS will run in parallel with PASS, to date, BFS has never been engaged to take over control from PASS during any shuttle mission.
The software for the shuttle computers is written in a high-level language called HAL/S, somewhat similar to PL/I. It is specifically designed for a real time embedded system environment.

The IBM AP-101 computers originally had about 424 kilobytes of magnetic core memory each. The CPU could process about 400,000 instructions per second. They have no hard disk drive, and load software from magnetic tape cartridges.

In 1990, the original computers were replaced with an upgraded model AP-101S, which has about 2.5 times the memory capacity (about 1 megabyte) and three times the processor speed (about 1.2 million instructions per second). The memory was changed from magnetic core to semiconductor with battery backup.
 
The F-22 has been in development since the early 90's, so I suppose it is possible.

Um, you mean the early 80's? There were F-22s flying before you were born, and I played video games with F-22s when I was little.

The F-22 is an ancient aircraft. There are F-16 variants out there that are more modern. Sure, it kicks butt, but so does just about any fighter jet. My iphone is MUCH newer than the F-22.
 
Um, you mean the early 80's? There were F-22s flying before you were born, and I played video games with F-22s when I was little.

The F-22 is an ancient aircraft. There are F-16 variants out there that are more modern. Sure, it kicks butt, but so does just about any fighter jet. My iphone is MUCH newer than the F-22.
Yeah, my bad. I knew the concept had been around a while, but I wasn't sure when it became the F-22. My cousin has an older die-cast model of an F-22 from before it went into production that says "YF-22 Black Widow II" on it. I told him it was labeled wrong and he just called me a nerd.:mixedsmi:
 
Yeah, my bad. I knew the concept had been around a while, but I wasn't sure when it became the F-22. My cousin has an older die-cast model of an F-22 from before it went into production that says "YF-22 Black Widow II" on it. I told him it was labeled wrong and he just called me a nerd.:mixedsmi:

It's essentially the same plane, as it's undergone many name changes for publicity. It used to be the YF-22, the F/A-22, the FA-22, and now it's just the F-22 again because they realized that they could never deliver it in a timely fashion with it's bomb dropping capability in a timely fashion. There are Raptors that drop bombs, but there aren't many.

I do'nt think it was ever called the black widow though. I could be wrong. As far as I know, that was only the YF-23, which many considered the superior aircraft of the two.
 
I can vouch for car computers from the 1980's. I was on a new team called OBED or OBDE, a super sophisticated engine management system that knew and calculated engine tuning via air temperature, thickness (altitude) engine temperature and needs, etc, etc, etc. It was amazing to monitor on a laptop as we did severe traffic day in and day out. How it could do all of that amazed me. It reminded me of a simple animal that was thinking. It had 3 sections in the master program, and I have no idea how they all talked to each other.


Then.....

There was the Porsche designed ABS braking computer system that could steer you through a turn in a dirt road with full breaks applied... (how???)

....and Air Suspension Management computer with built in 'modes management and speeds/handling requirements monitoring' as well as pot-hole dampening management (stemmed from Active Suspension from Lotus)..

And the Body computer, (your left door is open, and the kid in back seat left side spilled his coke again) which monitored things like 'turn off dome lights if they have been on for 2 hours to keep battery from dying' scenario.



That was back in the 1980's. Who knows what they are doing now, keyless ignitions that use your fingertip to identify and bring engine/motor and systems online, blue tooth everything, internet links and nav systems, AC systems that monitor front left, front right, rear left, etc... Some incredible technologies out there. I wish small planes could catch up to cars. If only someone like BMW would start making a GA plane... (or a Space Shuttle..! )


Bill
 
The product cycles on airplanes are a bit longer than on cars as is the demand for relaiability.

If your 200x [manufacturer] [model] breaks down on the road due to a computer error you just haul it back into the next garage and do a reset. If this happens to an aircraft in flight you'll need a whole army of helpers to scrape up the remains.

Heck, I think even my mobile phone has more calculating power than the F-22's computers!
 
I can vouch for car computers from the 1980's. I was on a new team called OBED or OBDE, a super sophisticated engine management system that knew and calculated engine tuning via air temperature, thickness (altitude) engine temperature and needs, etc, etc, etc. It was amazing to monitor on a laptop as we did severe traffic day in and day out. How it could do all of that amazed me. It reminded me of a simple animal that was thinking. It had 3 sections in the master program, and I have no idea how they all talked to each other.


Then.....

There was the Porsche designed ABS braking computer system that could steer you through a turn in a dirt road with full breaks applied... (how???)

....and Air Suspension Management computer with built in 'modes management and speeds/handling requirements monitoring' as well as pot-hole dampening management (stemmed from Active Suspension from Lotus)..

And the Body computer, (your left door is open, and the kid in back seat left side spilled his coke again) which monitored things like 'turn off dome lights if they have been on for 2 hours to keep battery from dying' scenario.



That was back in the 1980's. Who knows what they are doing now, keyless ignitions that use your fingertip to identify and bring engine/motor and systems online, blue tooth everything, internet links and nav systems, AC systems that monitor front left, front right, rear left, etc... Some incredible technologies out there. I wish small planes could catch up to cars. If only someone like BMW would start making a GA plane... (or a Space Shuttle..! )


Bill

That's cool stuff, but having been built a few modern motors and worked on aircraft, it's the ingenuity of guys such as yourself and not the computing that's impressive in those cases.

Take MAP/MAF or even speed density calculations. Is the computer really doing that much? Is it really that impressive? No, but I'll bet that it was a pain the butt to build and get going. coupling fuel injection with ECUs is possibly the greatest feat of automotive engineering in the last sixty years, and all it really takes is a little calculator.
 
I wish small planes could catch up to cars. If only someone like BMW would start making a GA plane... (or a Space Shuttle..! )
Are you kidding?!?! I wouldn't buy a BMW anything escpecially a plane. Maybe then all the Armenains in my town will fly around in BMW shuttles!
For small aircraft, it's all about simplicity. Or it should be.
Oh, and with BMW's new artist, that plane will look like a penis...
 
I wish small planes could catch up to cars. If only someone like BMW would start making a GA plane... (or a Space Shuttle..!


They really have. That's how Cirrus stepped in and grabbed a gigantic marketshare so fast. They produced a competitively-priced aircraft that blows Cessna 172s (and 182s, for that matter) out of the market. Everything about it is comfortable, high tech and perfectly engineered.
 
They really have. That's how Cirrus stepped in and grabbed a gigantic marketshare so fast. They produced a competitively-priced aircraft that blows Cessna 172s (and 182s, for that matter) out of the market. Everything about it is comfortable, high tech and perfectly engineered.

Except if you spin it, and upon the event of the CAPS failure the only thing you're going to be blowing is a hole in the ground.

If a perfectly engineered aircraft is one that is marketed to new flyers and through testing demonstrated that it has impossible spin recovery characteristics, keep me away from perfectly engineered planes!

Also, you can forget short field performance.

I'd rather have a new 172 over a Cirrus anyday. Much more flexible, just as comfortable, can do more places, have relatively simple stall/spin procedures, and probably cheaper (looking it up now). Little bit slower? So what, enjoy the view.
 
... If your 200x [manufacturer] [model] breaks down on the road due to a computer error you just haul it back into the next garage and do a reset. If this happens to an aircraft in flight you'll need a whole army of helpers to scrape up the remains...

A co-worker of mine was on the first flight of the first of a new model, I think it was a 777, owned by that particular airline.

They had everyone on board, and I believe switched to internal power, when the captian came on the intercom and annonced they had a red light on the panel, and needed to check it out.

He then saw a ground crewman walk up to the plane underneath his window. He opened up a panel, pulled out a keyboard, and pressed some keys.

The lights and A/C inside the cabin flickered on and off. A few moments later, the ground crewman got the confirmation from the captain that all was well, put the keyboard up, closed the panel, and gave a thumbs up as he walked away.

Yep, he had rebooted the airplane's computers! The captain came on informing everyone they were good to go, and away they went.

-James
 
Yep, he had rebooted the airplane's computers! The captain came on informing everyone they were good to go, and away they went.

Sometimes a reboot or thorough kick is the best solution for computer trouble. :d
 
Back
Top