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#61
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In message , Kevin Brooks
writes "John Cook" wrote in message .. . I've tried, and so far I can't find a single reference to an F-22 dropping any Bombs (JDAM or dumb), in fact theres only one recorded ground attack on record for the F-22 and that was due to a PIO error. Your whining is ceaseless in this regard. The USAF says the F/A-22 is JDAM capable. LMCO says it is JDAM capable. Hell, even Wikipedia says it is JDAM capable, IIRC! It flew the JDAM-capable Block 3.1 software back in 2002. You don't think it is JDAM capable--seems like you are in a distinct minority. When was the release clearance granted? "Capable" can mean as little as "1760 bus, and 14-inch lugs stressed for the weight". Sometimes it can mean less than that. Eight years ago I helped with a request from an aircraft manufacturer who for years had been widely advertising their maritime-patrol aircraft as "Sting Ray capable": it was only when they had a potential sale to a Sting Ray user that they bothered to talk to the manufacturer to find out what that claim would actually *mean* and what modifications to the weapon carriers were needed so that the potential customer could put their torpedoes on the aircraft. The sale didn't go through, they never modified the aircraft, it couldn't use Sting Ray as is, and yet it's *still* listed as Sting Ray capable despite the fact that it could only haul the torpedoes as jettisonable ballast: couldn't preset them, arm them or have them start up once in the water. (Maybe they could get the parachutes to open after release, but that's all) So take 'capable' with a generous pinch of salt. I'm sure the dummy JDAMs fit the bay: hopefully the wiring harnesses reach the relevant connectors within the snatch cone and with the correct lanyard angle, there are EMRUs or similar for the arming wires, and the drop characteristics have been properly explored to ensure the weapons will leave the bay cleanly across a range of airspeeds and attitudes (a frequent problem with bay-mounted weapons in fast jets). However, there's nothing mentioning any of this on the Web that I could find, other than the cheerful comment that the F-22 is 'JDAM capable'. Some flight and drop tests would help turn the notional "capability" into operational utility... so when were they carried out? -- When you have to kill a man, it costs nothing to be polite. W S Churchill Paul J. Adam MainBoxatjrwlynch[dot]demon{dot}co(.)uk |
#62
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In article , John Cook
wrote: So the processors are obsolete, (too old)... the Avionic architecture needs to be replaced before the F-22 can become the F/A-22 because the present system is based on the old processors and rewriting the code is pointless on an obsolete system, that would only support half of the F-22 fleet Methinks there's some confusion there between processors, avionics architecture, and software. While it's true that Intel tried to shut down i960 production causing a chinese fire drill, there are enough assets to get by until a new processor is ready. That has nothing to do with the avionics architecture, which is not changing. Plus the whole point of writing all the OS and AS in Ada was to be as platform independent as possible, so that upgrades to the CIP could be relatively painless and not force re-flight testing of the A/C. Ideally, one would not re-write the code, but re-compile the code for the new platform, then do a LOT of integrity checks, and take it from there... The question is does this 'new' processor conform to the 3 F's, Form Fit and Function?, If not then the processor demands a new architecture to support it, with the new architecture comes the the burden of porting it over, couple that with the reliability problems now being experienced and you have a flakey system thats being ported. AFAIK there is no 3F for the i960, therefor the system has quite neatly side stepped the reletivly painless CIP upgrade path. The CIP architecture from day 1 was designed to support incremental upgrades, but at the LRM level, not the component level as you imply. Each LRM (Line Replaceable Module for those who don't know) has a complete standalone interface to the avionics system, so if you change part or all of the card, the system should not know. So the hardware does have form, fit, and function upgradeability. The real issue under these conditions is software portability. The F-22 is under enormous pressure to perform right now, with the review reporting back in the next few months, any talk of obsolete systems in the state of the art jet are being downplayed. Upgrading obsolete parts was also a concern from Day 1. It was expected and planned for: it was one of the drivers for this implementation of the Pave Pace architecture. They have to go with a more COTS based system (similar to, if not the same as the JSF), which they are working on now, for fielding in (very optomisticlly) in 2007. Other than using commercialy available processor chips, what is "COTS" about it? Hint - nothing. Other than the Raptors costs its the cheapest fighter in the world... seriously the F-22 team will be levering the development work on the JSF for all its worth, anything to shove costs away from the f-22 program. The question asked above says that the F-35 system is more COTS than the F-22, and I dispute that. When people talk COTS wrt avionics I usually start laughing, most have no idea what they are talking about. Present company excluded of course. If you take a pile of commercial parts and custom design an embedded processing system for an aircraft, is the results a COTS system? It uses COTS parts, so it must be, right? But is the system available commercially? No. Is it off the shelf? Hell no. So how is it COTS? It's not. But is uses COTS parts. The F-22 hardware uses COTS parts packaged in a way that will function in an avionics environment. The F-35 hardware uses COTS parts packaged in a way that will function in an avionics environment. How is one more COTS that the other? What is the new processor? I always thought that a federated system had certain advantages with regard to upgradeing. Moto-based processors were tried. I don't know what the current vector is, I'm on different programs, but I expect they'll eventually settle on a G5 or better. Other facts (what a concept in RAM) The F-22 is also based on commercialy available processor chips (but not a commercial architecture) Avionics systems require a much higher level of security and determinism than any "COTS" package will ever offer. COTS is not necessarily cheaper when talking avionics COTS is one of those words that everyone thinks they understand, until it comes down to brass tacks. A simple analogy for you, the old 486 computer still works, but when I wanted to run XP on it the demands of the system increased to the point where it was useless to try, and you couldn't buy a 486 processor anywhere to support it. I call that an 'obsolete system', it worked great running win 98. Your analogy is seriously flawed for several reasons: A processor does not stand alone, it's part of a system, and many, many other things affect the system performance besides processor speed. Backside bus bandwidth, memory architecture, frontside bus bandwidth, etc. Plus the system in this case contains MANY processors in parallel. The system is officially termed a heterogeneous multi-processing system which means that it has several different kinds of processors as well as the i960, and all running in parallel. I think someone calculated the actual processing resources are equal to 2 Cray Y-MP supercomputers. Software also matters. Comparing avionics software to microS's bloatware is ludicrous. It was a simple analogy, not designed to compare avionics and M$ code, but to show why an upgrade is required, if it can't hack the requirements it needs upgrading, its that simple, If it can hack it, no upgrade is required - simple as that. Not as simple as that. The point I tried to make is that an adequate system overburdened with bloatware will not work and someone will point the finger at the hardware when the problem is in fact the software. Now the Raptor can't run the software to do its air to ground mission for the same reasons what would you call it?. "processor challenged???" I'd say, take a hard look at the above assertation and explain how it can be true, given that other AESA radars, in service, and with smaller avionics processors, don't seem to be having these problems. Take it up with the USAF, their requirements call for a certain level of capability in the AtoG role, the F-22 currently does not have the software or the hardware to fullfill that capability - hence the need for upgrades, what other reason is there for an upgrade...?. I'll agree that it doesn't have all the software. BTW, I worked on AFT, F-22, and several other current AESA programs, including airborne processors, and integrated avionics systems. Great, here' s a couple of questions for you. Do you think they will combine the AESA antennas for the JSF and the F-22 to a common 1200 module system? (I saw the number of modules for the F-22 was at 1500). I had heard a rumour that this was on the cards for cost savings etc. I can not comment on that for security reasons, but I did hear the same thing. Why is the Raptors Software so troubled?. You are asking me to pubically bash my customer. -- Harry Andreas Engineering raconteur |
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"Harry Andreas" wrote in message ... In article , "Tarver Engineering" wrote: The primary processor in CIP is the Intel i960MX microprocessor,which is used strictly for avionics processing. Pretty obvious I think. Yep, you somehow believe because Phill Miller is clueless, others must be clueless as well. I was correct and what Felger wrote is wrong. I do wonder at Phil's reading disability sometimes. The i960 has no application outside Lockmart's MPP. Not true. The i960 was used on several other programs. I worked on some of them myself. We have several statements including the GAO claiming that the i960 is now F-22 only. I stated in my other posts that the i960 was a printer control processor in the real world.(so obsolete) The real problem for Lockmart is that they are attempting to build an MPP that Intel could not build themselves and the continueing structure risk mitigation. |
#64
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"Harry Andreas" wrote in message ... In article , "Tarver Engineering" wrote: "Felger Carbon" wrote in message link.net... "Harry Andreas" wrote in message ... In article , John Cook wrote: Just the official reports!!, Lockheed has only purchased enough processors for 155 F-22's because there out of production, the demand for Air to ground operations has increased the demand on processing power, something the original processors are not quite upto hence the _need_ for the 'upgrade'. So the processors are obsolete, (too old)... the Avionic architecture needs to be replaced before the F-22 can become the F/A-22 because the present system is based on the old processors and rewriting the code is pointless on an obsolete system, that would only support half of the F-22 fleet Methinks there's some confusion there between processors, avionics architecture, and software. While it's true that Intel tried to shut down i960 production causing a chinese fire drill, there are enough assets to get by until a new processor is ready. Full disclosu I'm a retired electrical engineer. I specialized in high-end embedded microprocessors, which the "i960" in the F-22 is. I know nothing about designing aircraft. I do know a little about the Intel processor at the heart of the F-22: The i960MX was designed by Intel specifically and solely for the F-22. Nope, the i960 is a processor designed to control printers. There were several flavors of the i960, most of which were purely commercial and were used as printer drivers among other things. The i960 is the follow on of the i860, from which Intel produced the i432 MPP. The i432 was such a failure that Intel was nearly bankrupt and was forced to sell a controlling interest of 16% of Intel to IBM; it was through this transaction that IBM was able to corner the 8088 market. The i960 found application as a printer processor in the commercial world until some years ago. Lockmart got the bright idea of using the i960 to replicate Intel's i432 MPP success in the Raptor. snip of Harry making things up |
#65
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In article , John Cook
wrote: Harry Quick question - I just read that F-22 crew now carry cell phones for when the systems go down, so they can talk to ground control, is this true?? LOL, I have not heard that. But then again, like I said, I'm working other programs, not F-22. I'l ask the F-22 crew if they/ve heard that one. -- Harry Andreas Engineering raconteur |
#66
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"John Cook" wrote in message ... Cite please, where the evidence?. USAF. Do your own Google. I've tried, and so far I can't find a single reference to an F-22 dropping any Bombs (JDAM or dumb), in fact theres only one recorded ground attack on record for the F-22 and that was due to a PIO error. ;-) You might want to check back to March of 2003 when the Raptor failed to deliver the new joint standoff munition for the third time. It is public record. |
#67
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In article , "Tarver Engineering"
wrote: "Harry Andreas" wrote in message ... In article , John Cook wrote: Just the official reports!!, Lockheed has only purchased enough processors for 155 F-22's because there out of production, the demand for Air to ground operations has increased the demand on processing power, something the original processors are not quite upto hence the _need_ for the 'upgrade'. So the processors are obsolete, (too old)... the Avionic architecture needs to be replaced before the F-22 can become the F/A-22 because the present system is based on the old processors and rewriting the code is pointless on an obsolete system, that would only support half of the F-22 fleet Methinks there's some confusion there between processors, avionics architecture, and software. While it's true that Intel tried to shut down i960 production causing a chinese fire drill, there are enough assets to get by until a new processor is ready. Intel has agreed to provide mil-spec i960s, thanks to a very fat check from USAF. The new processor has already failed to be integrated, due to a loss of tracability. (ie scrap) That has nothing to do with the avionics architecture, which is not changing. Plus the whole point of writing all the OS and AS in Ada was to be as platform independent as possible, so that upgrades to the CIP could be relatively painless and not force re-flight testing of the A/C. Ideally, one would not re-write the code, but re-compile the code for the new platform, then do a LOT of integrity checks, and take it from there... They have to go with a more COTS based system (similar to, if not the same as the JSF), which they are working on now, for fielding in (very optomisticlly) in 2007. Other than using commercialy available processor chips, what is "COTS" about it? Hint - nothing. Wrong. Name for us the one and only modern processor that is mil-spec, Harry. You have my comment exactly backwards. I claim that JSF is NOT more COTS that F-22 because F-22 is using commercial parts, too. And that JSF is taking commercial parts and building a full mil-spec system, the end item being non-COTS, although made from COTS parts. The usual process since the early 90's. -- Harry Andreas Engineering raconteur |
#68
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"Harry Andreas" wrote in message ... In article , John Cook wrote: So the processors are obsolete, (too old)... the Avionic architecture needs to be replaced before the F-22 can become the F/A-22 because the present system is based on the old processors and rewriting the code is pointless on an obsolete system, that would only support half of the F-22 fleet does have form, fit, and function upgradeability. The real issue under these conditions is software portability. The software will not be portable, as timing issues will make that impossible. The F-22 is under enormous pressure to perform right now, with the review reporting back in the next few months, any talk of obsolete systems in the state of the art jet are being downplayed. Upgrading obsolete parts was also a concern from Day 1. It was expected and planned for: it was one of the drivers for this implementation of the Pave Pace architecture. snip Why is the Raptors Software so troubled?. You are asking me to pubically bash my customer. The GAO has already injected reality, but you should hush, Harry. If you bash the customer you are a bad guy, but if you continue down a road of telling what you know is subjective spin you will be unethical; the former is at least a recoverable fault. |
#69
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"Harry Andreas" wrote in message ... In article , "Tarver Engineering" wrote: "Harry Andreas" wrote in message ... In article , John Cook wrote: Just the official reports!!, Lockheed has only purchased enough processors for 155 F-22's because there out of production, the demand for Air to ground operations has increased the demand on processing power, something the original processors are not quite upto hence the _need_ for the 'upgrade'. So the processors are obsolete, (too old)... the Avionic architecture needs to be replaced before the F-22 can become the F/A-22 because the present system is based on the old processors and rewriting the code is pointless on an obsolete system, that would only support half of the F-22 fleet Methinks there's some confusion there between processors, avionics architecture, and software. While it's true that Intel tried to shut down i960 production causing a chinese fire drill, there are enough assets to get by until a new processor is ready. Intel has agreed to provide mil-spec i960s, thanks to a very fat check from USAF. The new processor has already failed to be integrated, due to a loss of tracability. (ie scrap) That has nothing to do with the avionics architecture, which is not changing. Plus the whole point of writing all the OS and AS in Ada was to be as platform independent as possible, so that upgrades to the CIP could be relatively painless and not force re-flight testing of the A/C. Ideally, one would not re-write the code, but re-compile the code for the new platform, then do a LOT of integrity checks, and take it from there... They have to go with a more COTS based system (similar to, if not the same as the JSF), which they are working on now, for fielding in (very optomisticlly) in 2007. Other than using commercialy available processor chips, what is "COTS" about it? Hint - nothing. Wrong. Name for us the one and only modern processor that is mil-spec, Harry. You have my comment exactly backwards. I claim that JSF is NOT more COTS that F-22 because F-22 is using commercial parts, too. Steidel was at F-35 after his successful engagement at F/A-18E. COTS is a disaster waiting to happen without the constraints of the RPL Model. The first thing Lockheed did when they got Power PC processors in was lose tracability. They do not even have the dicipline to control Mil-Spec parts, how can anyone expect them to understand the new reality? And that JSF is taking commercial parts and building a full mil-spec system, the end item being non-COTS, although made from COTS parts. The RPL Model is all there is, incarnations available from Federal Electric Corporation, Rome Labs and SAE's as AS9100 large shop adaptation. (see new CFR14 Part 145) The usual process since the early 90's. You are way behind the power curve Harry. Have a look at the fleet numbers for reliabilty for the F/A-18E vs the F-14s. Think about how the F-22's target number compares. |
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"Harry Andreas" wrote in message ... In article , "Kevin Brooks" wrote: "D. Strang" wrote in message news:1%obc.4658$zc1.3787@okepread03... The F/A-22 also has an inherent air-to-surface capability." It can already lug a couple of JDAM's. So how does that even *require* an optimized ground mapping radar to allow it to strike ground targets with significant precision? I'm not a bombardier, but I think the SAR radar is necessary for the INS inputs. The INS being only updated by the GPS, and only if the GPS isn't being jammed (which will be unlikely down the road). I think I read where GPS only doubles the accuracy of the INS (50 feet versus 100 feet). Without SAR, and GPS being jammed, you'll need a good pair of TACAN's, which some enemies don't seem to provide :-) I have yet to hear that a SAR update is required. Doing so would require the preloaded data for the terrain (so that the SAR would have something to relate its picture to). From what i understand, the weapon gets its update from the aircraft (through its own INS), then after release it uses GPS to improve the accuracy of its own INS. If SAR was required, then I guess the A-10 would never be certified to carry JDAM...? That's ridculous. No, what is ridiculous is your misunderstanding of my statement. As you acknowledge later, SAR is NOT required to launch a JDAM. And correct me if I am wrong, but you do indeed have to have a digital terrain model data set loaded in order to use the SAR to update a location--merely looking at the screen and saying, "Yep, that's a bridge!" doesn't cut it--the system would have to know that the bridge is at (insert 10 digit grid for centerpoint), either by vurtue of having access to a DTM or by inputting the accurate coordinates? The following article indicates that the basic procedure for JDAMS usage is as I described it--the carrying platform updates the weapon through both its own INS and GPS systems; use of a SAR, as in the case of the B-2 JDAM usage in Kosovo and Afghanistan, does indeed increase the accuracy further. http://www.aero.org/publications/cro...er2002/05.html SAR updates to pre-programmed INS settings have been used since the early 90's to improve the accuracy of GPS aided munitions. Uhmmm...Harry, what GPS guided munitions were in service during the "early 90's"? JDAMS was not; perhaps the ALCM or SLCM used GPS updates in conjunction with their stored DTM (but there you go again, that pesky DTM...); I can't think of any others that used GPS during that timeframe. You don't need the SAR update to launch a JDAM, but it dramatically improves the CEP of the weapon and essentially means that you can use a smaller weapon to take out a target. Well, it improves it, but not sure how "dramatically"; dramatic improvement of JDAMS appears to be dependent upon use of a secondary IR imaging system (DAMASK) or ISAR input after the drop, as was tested in the joint F-16 dropped, and E-8 updated AMSTE (Affordable Moving Surface Target Engagement) JDAM. Brooks -- Harry Andreas Engineering raconteur |
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