Thanks, the second post provided more info. However, I am still lost as far as: "But its use to FLY a plane is a solution looking for a problem
So, I did a little digging:
* AESA, in 2008 (today it is better):
The capability of that mode encompasses a range of potential operations, from one-way broadcasts to interleaved "fully duplexed" exchanges between two stations, said Dave Robbins, an engineering lead for R-CDL at L-3 Communications.
Raytheon has demonstrated the system can transmit data at rates of 274 megabytes a second — "a speed that starts to approach instantaneous," said Mike Henchey, Raytheon’s director of strategy and business development, Tactical Airborne Systems. It is a speed that easily eclipsed the current military standard. "If you are relying on a tactical data link like Link 16, it might take you close to an hour to get a 72-megabyte file off of the aircraft," said Carmichael. With R-CDL, that transmission "is a matter of 3 to 5 seconds," he said.
* Talking of "tactical data link Link 16": Per Wiki, it is "near real-time".
* As I mentioned India has been at this Fly
by Light since around 1997ish. So:Dec, 2002 :: CSIO develops fly-by-light controls for ALH
Chandigarh, December 22
A hi-tech fly-by-light (FBL) system for the Advance Light Helicopter (ALH) has been developed by the Central Scientific Instruments Organisation (CSIO) here. A team of scientists left for Bangalore this week to install the system in the aircraft for trials.
The FBL is used for sending signals from the cockpit to various instruments and sub-systems which control flight parameters of an aircraft. The ALH, developed indigenously by the Defence Research and Development Organisation, is undergoing user trials with the IAF and the Navy. All three services will have their own versions.
Sources told TNS that the project, initiated last year, was completed some time ago, but non-availability of an ALH had held up trials. The system will enter production once it is cleared and an indigenously produced unit is expected to cost as little as Rs 50,000-60,000, a top CSIO official said. The system would also be modified to be installed in other choppers in service with the forces, including the Chetak and the Mil series.
The FBL system is a further development of the now commonly used fly-by-wire (FBW) system. While signals are transmitted through electrical impulses to various control surfaces from the cockpit in an FBW system, the same is done through light impulses passed via Optical Fibre Cables (OFC) in the FBL system. Prior to the development of these two systems, the controls were operated mechanically.
The ALH will be the first Indian aircraft to be equipped with the fly-by-light system. Even the Light Combat Aircraft (LCA), which made its maiden flight earlier this year, is equipped with a fly-by-wire system. While the technology was earlier restricted to combat aircraft, now civilian airliners, specially the Airbus series, also incorporate the Fly-by-Wire system.
The use of optical fibre cables, instead of copper wires, gives the FBL system several advantages over the FBW system. Besides being considerably lighter and cheaper, the FBL systems had the capacity of transmitting a greater number of signals and data simultaneously. Moreover, optical fibre cables are immune to electro-magnetic interference or electrical conduction and result in better gyro control of an aircraft.
As far as the working principle of the system is concerned, experts say that in FBL systems, signals from the cockpit are converted into light impulses and focussed on the control surface concerned. Control signals between the pilot stations, flight control computer and actuators for rotor blade controls are not transmitted electrically, via wire, but optically, via hair-thin optical glass fibres.
* As far as I know there is a diff between commercial and military networks. I am fairly confident that the Indians are catching up, but, for sure the good guys deal with huge data needs. There are some cases where terabytes
* Found out that the US conducted extensive research in *Fly* by Light (I did not even know there was a *Flight* by Light - what is that I wonder) in the 80s. They never implemented it in the military side. Looks like it was not so much to do with technology as much as cost. They then did not have the amount of data they have now. So, I am told (I have not verified it yet) that they are trying the FbL technologies on UAVs first before porting it over to manned machines
* Finally, the AMCA has been under construction for a very long time. And, from day 1 they have been talking of FbL and they have not backed out ----- yet. It is specifically WRT this point that I ask "What gives" (and not your or anyone else experience - which is very important). The AMCA team had a team exclusively for human-machine interface, they built (per open source) a complete cockpit - with a panoramic display, no button or dials, etc (I do not know where all stands today or even if they have retained it in their current plans - just that that was the last data point I have). Point being they have invested some 15 years +/- some in a variety of technologies, which IMHO, cannot be discounted. ???? Will they come to fruition? I certainly hope so. Am I certain? No. But, I do think these technologies will - I cannot find a good reason not to