Helmet-mounted displays

[spazsinbad]

Perhaps reducing the weight of the HMDS may help - surely the topic of this thread - but weight related the F-35B engine thrust was increased by a small amount some years ago now. Perhaps if HMDS related topics could be discussed on this thread - that would be nice? Whilst the F-35B engine thrust could be elsewhere? Perhaps on a thread dedicated to that point?

[neurotech]

Yeah, I must confess I do get off topic sometimes

Ill see if I can find recent updates on the overall weight reduction, and then post a new topic.

[marksengineer]

Neurotech:

A bit off topic but in response to your post doesn't the Navy have 3 Expeditionary EA-18G squadrons? Thought the AF funded enough EA-18G's for 4 units?

[spazsinbad]

Back on topic:

F-35B grounded, Lockheed responds to DOT&E report By Dave Majumdar on January 18, 2013

http://www.flightglobal.com/blogs/the-d ... espon.html

"...One thing not in the story is the F-35's vital helmet mounted display. O'Bryan said that he couldn't directly address the current issues with the helmet. But he did say that we can expect an announcement from the F-35 JPO within the next two months about where the program is on fixing the helmet. The only thing he is able to say is that a new ISIE-11 night vision camera will be cut into production in LRIP 7--which VSI had told me earlier is hoped will remedy night vision acuity problems. The ISIE-11 will be replacing the older ISIE-10 camera that is on the current jets."

[munny]

A spot of reading on Intevac night vision cameras using their ISIE-10 and ISIE-11 sensors.

Basically 50% higher pixel count, double the frame rate and better processing.

http://www.intevac.com/intevacphotonics ... ightvista/

Video of the old ISIE-10 sensor in action...

http://www.intevac.com/intevacphotonics ... n-setting/

Extremely low light ISIE-10 demo

http://www.intevac.com/intevacphotonics ... l-setting/


Datasheet for ISIE-11 based camera

http://www.intevac.com/wp-content/uploa ... sheet1.pdf

[spazsinbad]

Thanks 'munny' here is a compare graphic: http://www.intevac.com/intevacphotonics ... ightvista/

[spazsinbad]

F-35 JSF Testers Report Progress, Problems By Guy Norris, Graham Warwick — With Amy Butler and Bill Sweetman in Washington. Source: Aviation Week & Space Technology 21 Jan 2013

http://www.aviationweek.com/Article.asp ... 03.xml&p=3

"...“We have done a lot of night flying to understand the helmet and DAS [distributed aperture system], and done night hovering as well.” McFarlan says testing of the troubled helmet is making progress and now focusing on latency of the DAS imagery projected on the visor during night flying."

Lotsa bits and pieces excerpted elsewhere....

[neurotech]

Neurotech:

A bit off topic but in response to your post doesn't the Navy have 3 Expeditionary EA-18G squadrons? Thought the AF funded enough EA-18G's for 4 units?

6 Squadrons but only deploy on detachment, not complete squadrons usually. I think the AF funds their WSO/EWO crews, and maybe some of the detachment costs. It's entirely possible that the AF pays for 4 detachments of EA-18 operations. The AF didn't pay for the actual jets purchased.

[f-22lm]

Hello fellow members, I just want to give you guys the updated look on the helmet.





http://www.edwards.af.mil/shared/media/ ... 99-001.jpg

[spazsinbad]

Thanks. Must be the 'Son of Gums'? Salute.

[spazsinbad]

from the 'bumtish' post here: http://www.f-16.net/f-16_forum_viewtopic-t-23179.html

http://www.regjeringen.no/nb/dep/fd/tem ... ?id=715294 21 Feb 2013 Partner Presentation

One para 'translated': ..."- We see that progress with the helmet is now so good that [they/we] are likely to go back to one solution at the next major milestone in April, and [they/we] will then scrap the backup solution which began its work last year. A Lightning Protection solution has now been agreed on and restrictions on flights in thunder storms will be lifted in 2015, concurrently with software version "2B" being installed in the aircraft. This is the software the U.S. Marine Corps will be operational with in 2015, and where shortly after the use of F-35 in hot military operations if necessary. The development of software in general, where we previously saw a backlog has now been dealt with [caught up on], and the development of Block 2B software is now on track to be installed in 2015. This shows that the measures taken just months back, are now showing results, says Klever...."

[battleshipagincourt]

It's debatable if the F-35B would have been better with a modest thrust increase, instead of trying to reduce weight in areas that effect service life or survivability

That wasn't really an option. The F-35's STOVL capabilities weren't limited by their thrust to weight ratio, but by the lift fan's output. So even if the F-135 could deliver double its original thrust requirements, the fan was pretty much fixed.

So the only option beyond cutting off the excess fat was to either reduce its bring back or always stressing the STOVL system to its maximum capacity just to maintain a hover... which would reduce lifespan considerably.

[spazsinbad]

Tailored to Trap 01 Dec 2012 Frank Colucci

http://www.aviationtoday.com/av/militar ... 77964.html

"F-35C control laws give Navy pilots Integrated Direct Lift Control for easier carrier landings, and they open the door for future landing aids."...

"...Even with its innovative flight controls, the F-35C, from the pilot’s perspective, is relatively conventional coming aboard the carrier. “Determining where you are with respect to lineup and glideslope is all visual,” acknowledged Canin. “For lineup, you look at the ship and line up on centerline… easy enough if the ship’s heading is steady, but tricky if the ship is wallowing,” noted Canin. “As for glideslope, you have to watch the meatball and see small deviations. Then you have to put the ball back in the middle, with the right rate of descent so it stays there. None of that’s changed with this airplane, but what we’re giving the pilot is more responsiveness and bandwidth to do that.”

The F-35 uses a BAE Helmet Mounted Display (HMD) instead of a conventional Head-Up Display (HUD). Like a classic HUD, the HMD shows the pilot a flight path marker (or velocity vector), with a bracket to indicate if the aircraft is “on speed” or flying fast or slow. Meanwhile, a caret moves up or down in reference to the flight path marker to give an acceleration-deceleration cue.

Ashore, when the aircraft is on glideslope, the pilot simply puts the flight path marker by the meatball and the aircraft stays on that glideslope. “At the ship, since the landing area is moving through the water, the pilot needs to put the flight path marker out in front of it. He needs to put it where the landing area will be when he gets there, which again requires judgment. A better system would be put the velocity vector into the moving reference frame of the boat,” Canin said.

Though not currently part of the F-35 plan, implementing a “ship-referenced velocity vector” (SRVV) would allow the pilot to put the SRVV on the intended touchdown point to hold glideslope. “All we would need to know from the ship is its current velocity, so we can put the airplane symbology in that reference frame,” Canin said.

Readily rewritten control laws have other possibilities. “With the current flight control law, the pilot commands pitch rate with the stick, and uses that pitch rate to establish a glideslope,” noted Canin. “There’s no reason, though, why the flight control system couldn’t establish a baseline glideslope, and allow the pilot to apply control stick pressure to command tweaks around that glideslope in response to ball deviations.” A “glideslope command” mechanization of this sort is not in the baseline airplane now, but is an example of the type of changes that could relatively easily be incorporated in the F-35 control system....

...The JSF test program currently has no autolanding requirement, but plans call for an F-35C autolanding capability based on the Joint Precision Approach and Landing System. “The F-35 will take more of a self-contained approach — an internally generated glideslope from GPS.”

IDLC is just one part of the F-35 test program which will now include tests of a refined tailhook for arrested landings. “We look at approach handling qualities every chance we get,” said Canin. “Where the rubber meets the road, though, is at touchdown. Until recently we haven’t had a loads clearance that allowed us to do carrier-type landings, but now we do, so now we’ll be able to look at our control precision to touchdown.”

Canin concluded, “Carrier landings, particularly at night, are still considered to be the hardest thing to do in aviation. But I think we now have an airplane, and the people in our control laws group, that can kill that notion forever. The carrier approach is a very well-defined problem, and there’s no reason why this airplane can’t completely change the game.”"

As mentioned on two other recent threads on this forum, this article is long and complex with many different aspects suitable for the different threads.

Go to these forum URLs for these different relevant excerpts from same article:

http://www.f-16.net/f-16_forum_viewtopi ... t-105.html
&
http://www.f-16.net/f-16_forum_viewtopi ... t-315.html

[spazsinbad]

F-35 Program Status March 14, 2013

http://www.f-16.net/f-16_forum_download-id-17262.html (120Kb)

"...Helmet/Software
- Pilots have flown more than 4,000 flights and 5,000 hours with the helmet and our feedback from pilots at Edwards, PAX River, Eglin and Ft. Worth, is they love this helmet. During the fall, dedicated tests were performed testing the improvements we’ve made and the results are positive.

- Block 1 and 2A software is supporting pilot training at Eglin.The same software will also be used to support flight operations at Yuma. Successful test results in flight test are seen at both Edwards and PAX.

- Only 10 percent of the software is still in development...."

[spazsinbad]

Repeated from a "MADL" thread earlier: http://www.f-16.net/f-16_forum_viewtopic-t-23840.html

Lt General Christopher C. Bogdan Program Executive Officer F-35 SASC Written Testimony 24 Apr 2013

"...In addition to software challenges, the three F-35 variants are encountering the types of development problems typically experienced on advanced state-of-the-art, high performance aircraft development programs at this stage of maturity. While we still have technical risks on the program, I have confidence that the known technical issues we have will be solved and properly integrated into the F-35. The Helmet Mounted Display System (HMDS) for the F-35 is a major technological advance and a design challenge. Issues faced by the program office over the past year relative to the HMDS were “green glow” or insufficient helmet display contrast, latency of the displayed information, “jitter” or lack of stability of the displayed symbology, night vision acuity and alignment. We executed a short flight test program from November 2012 to March 2013 dedicated solely to exploring and understanding the helmet problems using developmental and operational test pilots flying a number of operationally representative missions. As a result of this testing, the program now understands and has mitigated the effects of ”green glow”, latency, jitter and alignment. Additional work still needs to be done to ensure that the program has a night vision camera that is effective for operations as our testing indicated that the current night vision camera is unsuitable for operational use. As risk reduction, the program continues to fund development of a night vision goggle-based alternative helmet solution. The goggle-based helmet development will continue until we see demonstrated improvement in all of the risk areas of the original helmet and until the government has secured a price agreement with the prime contractor showing significant cost reduction in the original helmet...."

http://www.armed-services.senate.gov/st ... -24-13.pdf (180Kb)