F-35 & stealth obsolescence?

[basher54321]

If the F-35 is using Fibre Channel with the 1553 command set then its a totally different network architecture to the original 1553 standard.

Bingo...1553 is an interface, not a bandwidth standard.
I doubt very much the US services would change its entire logistic by dumping 1553 just to accommodate some 'endemic' JSF standard.
JSF's optical wiring is also hardly news and EF (for one) is probably equally capable of streaming high bandwidth demanding streams like HD video and such.

MIL-STD-1553 defines the hardware and software protocol - and the data rates etc - Fibre Channel has nothing to do with it - only that you can still send 1553 commands over it.

MIL STD 1553.pdf

(565.21 KiB) Downloaded 1511 times

Interestingly the commercial world starting dumping Fibre Channel 5 years back and replacing it with iSCSI - so basically sending the SCSI commands over TCP/IP!


For jets that have fibre cabling installed already then yes the throughput can go way over 1GB/s - you just have to change all the hardware.
If they are using the twinax of the original 1553 then that High speed 1553 would need to be used.





I took this from a 2001 avionics handbook for the F-22 that shows its using 3 different protocols and thus different bandwidths on each segment:


The High-Speed Data Bus (HSDB) is a fiberoptic bus which provides 50 Mbps data transfer rate between the CIPs and the Data Transfer Cartridge or Mass Memory unit.

The Fiber Optic Transmit-Receive (FOTR) Bus supports low latency, high bandwidth (400 Mbps) data communications between the CIP and the sensors.

The Mil-Std 1553Bus provides I/O communications to standard interfaces such as weapons and aircraft flight control systems.



tbh I suspect 1GB is currently far more than F-35 needs at this moment in time.

[hornetfinn]

If the F-35 is using Fibre Channel with the 1553 command set then its a totally different network architecture to the original 1553 standard.

Bingo...1553 is an interface, not a bandwidth standard.
I doubt very much the US services would change its entire logistic by dumping 1553 just to accommodate some 'endemic' JSF standard.
JSF's optical wiring is also hardly news and EF (for one) is probably equally capable of streaming high bandwidth demanding streams like HD video and such.

MIL-STD-1553 is not an interface, it's a standard that defines electrical, mechanical and functional properties of a serial data bus. Those properties include bandwidth. There is a separate, but very closely related standard for MIL-STD-1553 command set using optical cabling, called MIL-STD-1773. STANAG 3910 is also a standard that explicitly states that it can transfer 20 Mbps.

[cola]

MIL-STD-1553 defines the hardware and software protocol - and the data rates etc - Fibre Channel has nothing to do with it - only that you can still send 1553 commands over it.

Well, to be perfectly clear, not exactly...important to emphasize is that 1553 is an interface, applicable via various bandwidths and therefore datarates.
Ofc, the OS (how the software handles hardware) will vary depending on speed (like ISDN and ADSL), but either way it's compatible towards out, which is why it's called MIL-STD.

For jets that have fibre cabling installed already then yes the throughput can go way over 1GB/s - you just have to change all the hardware.
If they are using the single core coax of the original 1553 then that High speed 1553 would need to be used.

Well, I don't think you have to change ALL hardware, perhaps only I/O circuit (I'm assuming actual 1553 hardware is way faster than any bus it gets installed onto), but yes you're generally right.

[basher54321]

Well, to be perfectly clear, not exactly...important to emphasize is that 1553 is an interface, applicable via various bandwidths and therefore datarates.
Ofc, the OS (how the software handles hardware) will vary depending on speed (like ISDN and ADSL), but either way it's compatible towards out, which is why it's called MIL-STD.

I see where you are coming from - thinking that just because 1553 runs over different network topologies its just an interface - however the MIL-STD-1553 standard is completely tied into the hardware (as per the pdf in the last post) - very clearly defined that in its a half duplex bus. The A and B revisions are very similar and also required specific hardware, and cabling types.

For STANAG 3910 - it is stated MIL STD 1553B was not deemed suitable - so it is using a revised 1553 interface and using new hardware and a reflexive star topology (note 1553A/B is a bus topology only) It works with existing 1553 commands sure - but it is not MIL-STD-1553 or MIL-STD-1553A or even MIL-STD-1553B any more than 100BaseFX Ethernet is the original 10Base2 Ethernet bus - totally different specifications, and different software and hardware required.

The command set alone does not make the entire protocol(or version of) - because it simply doesn't work without the defined hardware.

Here you go here are some MIL-STD-1553B coupler, cabling and connectors http://www.milestek.com/s-145-mil-std-1553b.aspx

Well, I don't think you have to change ALL hardware, perhaps only I/O circuit (I'm assuming actual 1553 hardware is way faster than any bus it gets installed onto), but yes you're generally right.

Depends - be nice if you could just slot in a different interface card with the different physical Fibre Optic interface on it - however not optimistic on this.

[cola]

The command set alone does not make the entire protocol(or version of) - because it simply doesn't work without the defined hardware.

True.
What I tried to emphasize is that it's 'command set' that makes 1553 and aircraft's FCC compatible with, say, AIM9, as opposed to how it operates internally (OS).

Depends - be nice if you could just slot in a different interface card with the different physical Fibre Optic interface on it - however not optimistic on this.

Indeed, in practice it's a bit more complicated than that, but note I used that example to emphasize the point probably exaggerating a bit...

[gtx]

F-35 will enjoy very serious SA advantage over any other fighter jet, most likely including F-22.

That's the thing that f-35 naysayers so often fail to get. They keep thinking the F-35 only has its stealth features. They deep missing the rest of the picture IMHO. The sensor suite and avionics package (especially the way information is presented to the pilot) are more impressive. F-35 pilots will have the advantage of knowing where their enemy are and doing whilst denying the same to the enemy. Its actually quite unfair…as if I cared.

[Gums]

Salute!

c'mon, folks.

The MIL-STD-1553 bus has been around since the 70's, and it was the primary buss used in the Viper and on other platforms. One megahertz, master bus controller and the slave remote units - command and response, with no voluntary messages by the remote units.

It's the buss that was used by the Slammer and other new stuff after the 70's, and was integral in MIL-STD-1760 and some other STANAG standards. The Viper had remote interface units ( RIU) at each store station and used the 1553 buss to command and recieve data and control functions. I happen to be part of the team that refined the 1760 standard store interface that used 1553 and then the fiber optic line ( 1773 at the time, but not clearly defined by the time I left the company late 90's). The 1760 store interface had DC, AC, muxbus, video line, and other electrical interfaces, plus standard mechanical connectors and such. It was developed and implemented for interoperability amongst the NATO folks. The standard also had very specific protocols for arming and firing/releasing ord - this was very important for the nukes, heh heh. Our Vipers were the first !!! And my company did the prototype Viper stores management system using the RIU concept and the 1553 buss in early 70's down here at Eglin.

I can tellya that the fiber optic line was super for data transfer to the weapon. We still had to have a dedicated "card" from the central fire control computer to the weapons, but the cabling was "standard", so we saved lottsa weight. We could download lottsa data very quickly compared to the 1553 with its 1 meg bus, plus not a lot of RIU's using the fiber optic line. Inertial alignment of a weapon was a bear using 1553, and this was important for JDAM, etc. With a host of avionics all using the basic 1553 buss, we had time problems due to the 32 data packets (max), so the central bus controller had to allocate data transfer according the the requirements of each system on the buss. Viper max frame rate was 50 hz, but most systems used lots less frame rates.

Gums recalls....

[loke]

Other aircraft certainly have sensor fusion and networking capabilities, but the F-35 goes "above and beyond," so to speak. For example, a 4.5 gen jet might have multiple sensors that are semi-fused together, but it isn't like the F-35, where all of the information is presented as a single track on a single display, and the onboard computer automatically chooses the best information. Also, most modern jets require the pilot to task various sensors, which becomes a bit of a pain when you've got a radar, IFF, IRST, MAWS, EW suite, targeting pod, etc. In contrast, the F-35's fusion engine not only correlates data, but automatically tasks each sensor without needing pilot input. For example, if the fusion engine is receiving information from the radar set, but determines it might be possible to get better angular resolution with the IRST (as in the example above), it will automatically slave the EOTS to the radar track.

I'm also not sure if legacy jets automatically incorporate wingman sensor inputs into their sensor fusion systems the same way the F-35 does.

Also, no other airplane (that I'm aware of) has anything like the DAS. With all other aircraft, a non-emitting target or a target with a LPI AESA can sneak up on it -- the only 360 degree sensor other aircraft posses is a EW suite. The F-35, in comparison, has a 360 degree sensor suite that can detect both emitting and non-emitting targets.

Rafale is perhaps the 4.5 gen fighter with the best "sensor fusion"; the swiss leaks indicated at least that the Swiss liked the sensor fusion of the Rafale whereas the Typhoon sensor fusion was found lacking. SH block II don't have sensor fusion AFAIK.

Based on the processing power of the MDPU modular mission computer, the data fusion performs the number crunching on data provided by the AESA radar, the FSO optronic system, the SPECTRA electronic warfare system, the data links, the IFF (friend-foe identification) interrogator and the infra-red missile seekers.

The data fusion yields a simplified and consolidated tactical picture, showing correlated system tracks rather than separate sensor and data link tracks. Workload alleviation, clarification of the tactical situation and fratricide risk reduction are the most immediate benefits for the RAFALE pilot.

Implementation of the “multi-sensor data fusion” into the RAFALE translates into accurate, reliable and strong tracks, uncluttered displays, reduced pilot workload, quicker pilot response, and eventually into increased
situational awareness.

It is a full automated process carried out in three steps:

1. Establishing consolidated track files and refining primary information provided by the sensors,

2. Overcoming individual sensor limitations related to wavelength / frequency, field of regard, angular and distance resolution, etc, by sharing track information received from all the sensors,

3. Assessing the confidence level of consolidated tracks, suppressing redundant track symbols and decluttering the displays.

This is still far away from what the F-35 will be able to do, still it's not too shabby for an old european fighter.

Rafale does not have EODAS of course, however the the two DDM NG offer some increased SA:

http://www.aviationweek.com/blogs.aspx? ... 6a84130efa

[basher54321]

Salute!

c'mon, folks.

The MIL-STD-1553 bus has been around since the 70's, and it was the primary buss used in the Viper and on other platforms. One megahertz, master bus controller and the slave remote units - command and response, with no voluntary messages by the remote units.

It's the buss that was used by the Slammer and other new stuff after the 70's, and was integral in MIL-STD-1760 and some other STANAG standards. The Viper had remote interface units ( RIU) at each store station and used the 1553 buss to command and recieve data and control functions. I happen to be part of the team that refined the 1760 standard store interface that used 1553 and then the fiber optic line ( 1773 at the time, but not clearly defined by the time I left the company late 90's). The 1760 store interface had DC, AC, muxbus, video line, and other electrical interfaces, plus standard mechanical connectors and such. It was developed and implemented for interoperability amongst the NATO folks. The standard also had very specific protocols for arming and firing/releasing ord - this was very important for the nukes, heh heh. Our Vipers were the first !!! And my company did the prototype Viper stores management system using the RIU concept and the 1553 buss in early 70's down here at Eglin.

I can tellya that the fiber optic line was super for data transfer to the weapon. We still had to have a dedicated "card" from the central fire control computer to the weapons, but the cabling was "standard", so we saved lottsa weight. We could download lottsa data very quickly compared to the 1553 with its 1 meg bus, plus not a lot of RIU's using the fiber optic line. Inertial alignment of a weapon was a bear using 1553, and this was important for JDAM, etc. With a host of avionics all using the basic 1553 buss, we had time problems due to the 32 data packets (max), so the central bus controller had to allocate data transfer according the the requirements of each system on the buss. Viper max frame rate was 50 hz, but most systems used lots less frame rates.

Gums recalls....

Thanks Gums......pretty useful and cleared a few things up - is there anything you haven't done

[basher54321]

Rafale is perhaps the 4.5 gen fighter with the best "sensor fusion"; the swiss leaks indicated at least that the Swiss liked the sensor fusion of the Rafale whereas the Typhoon sensor fusion was found lacking. SH block II don't have sensor fusion AFAIK.

Everything I can find points to Rafale using a version of STANAG 3910 like the EF. But 20Mbps is still okay the Rafale does have a good avionics set (Well according to the Swiss)

F-16EF has a degree of sensor fusion so I would certainly expect the FA-18EF to have it - and based on available info its got much faster throughput potential than the Euros...........

[Gums]

Salute!

All the bandwidth and such is great for graphics, video and mass data transfer ( big problem for 1553).

For data fusion, you really don't need very high bandwidth. Just think about graphics on your basic internet connection.

My concern is with specialized data busses and that folks may have trouble with "plug and play" subsystems. Many of us worked like hell to develop and implement the 1760 store interface software protocol, even using the slow 1553 buss. Further, many of the weapons from the early 70's had dedicated boxes and data lines - Harpoon, HARM, TOW, Hellfire, and the beat goes on.

So we developed remote terminals that could use the 1553 stuff to activate/control the electrical signals to make an old system work on a new jet, and vice versa. That was what my company did. If you folks saw the Hellfire and Maverick signal set, you would be shocked. So the Viper dudes had RIU's/RT's in the launcher to use the 1760 electrical wires, video line and such with 1553 commands. That was the model we used, and hell, we were the guys that came up with the idea. Duhhh?

For the F-35, initializing the JDAM and similar weapons really needs the bandwidth. I saw this first with the A-12 due to its internal carriage. Then the B-1 and the B-2. 1553 is very good for "control", but sucks for mass data transfer.

Gums sends....

@ basher Only thing I didn't do was command a space shuttle, and I joined because I wanted to fly into space. Oh well.....

[basher54321]

@ basher Only thing I didn't do was command a space shuttle, and I joined because I wanted to fly into space. Oh well.....

Nothing to regret considering everything else! and maybe the work on 1760 was worthwhile after all

This does mention 1760 is being used on the F-35 on the 6th from last page:

http://www.dtic.mil/ndia/2010armament/TuesdayLandmarkADougHayward.pdf


So I would say based on that and other clues that F-35 is still using 1760 for the stores - albeit a high speed 1760 version (SAE AS5653 ) 1Gbps over fibre. This interfaces to the 1553 over Fibre Channel (FC-AE-1553) network (also 1Gbps) that is used for avionics and FLCS etc - but can still act as bus controller for 1760 the same way legacy 1553/1773 did.

[neurotech]

Rafale is perhaps the 4.5 gen fighter with the best "sensor fusion"; the swiss leaks indicated at least that the Swiss liked the sensor fusion of the Rafale whereas the Typhoon sensor fusion was found lacking. SH block II don't have sensor fusion AFAIK.

Everything I can find points to Rafale using a version of STANAG 3910 like the EF. But 20Mbps is still okay the Rafale does have a good avionics set (Well according to the Swiss)

F-16EF has a degree of sensor fusion so I would certainly expect the FA-18EF to have it - and based on available info its got much faster throughput potential than the Euros...........

The standard F/A-18E/F Block II doesn't have sensor fusion, although the avionics bus isn't the limit. The APG-79 radar needs upgrades, and the baseline EW/RWR system wasn't fully integrated with the targeting. The EA-18G has integrated targeting for the ALQ-218s and limited sensor fusion with IR targeting pods. This is one reason why the Growler-Lite package is being looked at. They are upgrading the F/A-18E/F IRST.
http://defensetech.org/2014/03/18/fa-18 ... ng-sensor/
They are also upgrading the Advanced Mission Computer (AMC-4) for the F/A-18E/F & EA-18G which will boost capability. Sensor Fusion was planned for the F/A-18E/F Block III variants for India and Brazil.

The F-16E/F has sensor fusion and more importantly, IRST and EW systems are fully integrated, so sensor fusion on the Block 60 is more benefit to the pilot.

@gums: I remember emailing a friend who flew F-22s, and on his retirement the only thing he hadn't done in his career was eject out

[jimmer]

How does the USAF and Navy mitigate jamming their own radars when using various electronic warfare weapons?

[cantaz]

For data fusion, you really don't need very high bandwidth.

Would the F-35 be the exception? Since all processing and fusion is centralized, all the sensors are passing large volumes of raw data. Especially the DAS, with 6 imaging sensors operating simultaneously.