Helmet-mounted displays

Cockpit, radar, helmet-mounted display, and other avionics
  • Author
  • Message
Offline
User avatar

spazsinbad

Elite 5K

Elite 5K

  • Posts: 22854
  • Joined: 05 May 2009, 21:31
  • Location: ɐıןɐɹʇsn∀¯\_(ツ)_/¯
  • Warnings: -2

Unread post31 Oct 2012, 02:18

Thanks for explanation 'quicksilver'. Night vision unaided can play many tricks. Our eye will 'move around' a single light source attempting to determine distance or other details. If a single light in distance is stared at, after a few seconds it will start to rotate around a central point, which can be disconcerting if forming up in night formation. Probably slime lighting helps as your aircraft gets closer but I'm talking about when only a single light may be visible.

Being catapulted on a dark night with no visible horizon and a single light a long way ahead (fishing boat) can cause similar issues just after the shot (in my case causing extreme disorientation). Having even ghostly night vision, so as to have at least a horizon, or a vague aircraft shape (at distance) will help a great deal. USN aviators have been overwhelmingly positive in their published remarks about HMDS night vision (even before it has been improved).
RAN FAA A4G Skyhawk 1970s: https://www.faaaa.asn.au/spazsinbad-a4g/ AND https://www.youtube.com/channel/UCwqC_s6gcCVvG7NOge3qfAQ/
Offline
User avatar

Gums

Elite 2K

Elite 2K

  • Posts: 2271
  • Joined: 16 Dec 2003, 17:26

Unread post31 Oct 2012, 05:06

Salute!

Good dicussion, Quick.

And for Spaz - talk to one of the Hornet dudes down where you live about how neat a HUD was when coming off the cat on a dark, moonless night.

I fully understand the latency and frame rate requirements for a useful display, with about 1600 hours of "HUD" time in two different jets. And then as a systems engineer for cockpit controls and displays and weapon integration.

For the target acquisition and such, a slow update rate is fine. But for a "virtual" HUD when landing on a pitching/rolling carrier deck it's better to have not only decent update rates, but less dependency upon the helmet measurements and eye position that the F-35 uses. The virtual HUD now being used is certainly faster than a seventh of a second update rate. And the display rate is likely 20 msec or better ( Viper data bus in 1979 was 20 msec for most data). I posit that the helmet positional data rate is lots higher.

And BTW, I HAVE TALKED WITH a pilot or two at Eglin. They would not talk about the "jitter" with high AoA, but liked the thing for the most part. They especially liked the VSTOL view thru the floor!

Make no mistake. I am not a dinosaur WRT to new technology or displays. Hell, I flew the leading edge jet - the A-7D. We had more goodies than anything around for another ten years. I loved it.

My only concern is that a fairly cheap backup to the helmet might let the jet get on to operational status faster and cheaper. I also wonder how good the pilots will be when the helmet goes tango uniform and the pilot is basically flying steam gauges from 40 years ago.

Gums sends...
Gums
Viper pilot '79
"God in your guts, good men at your back, wings that stay on - and Tally Ho!"
Online

quicksilver

Elite 2K

Elite 2K

  • Posts: 2541
  • Joined: 16 Feb 2011, 01:30

Unread post31 Oct 2012, 12:57

Gums wrote:Salute!

Good dicussion, Quick.

And for Spaz - talk to one of the Hornet dudes down where you live about how neat a HUD was when coming off the cat on a dark, moonless night.

I fully understand the latency and frame rate requirements for a useful display, with about 1600 hours of "HUD" time in two different jets. And then as a systems engineer for cockpit controls and displays and weapon integration.

For the target acquisition and such, a slow update rate is fine. But for a "virtual" HUD when landing on a pitching/rolling carrier deck it's better to have not only decent update rates, but less dependency upon the helmet measurements and eye position that the F-35 uses. The virtual HUD now being used is certainly faster than a seventh of a second update rate. And the display rate is likely 20 msec or better ( Viper data bus in 1979 was 20 msec for most data). I posit that the helmet positional data rate is lots higher.

And BTW, I HAVE TALKED WITH a pilot or two at Eglin. They would not talk about the "jitter" with high AoA, but liked the thing for the most part. They especially liked the VSTOL view thru the floor!

Make no mistake. I am not a dinosaur WRT to new technology or displays. Hell, I flew the leading edge jet - the A-7D. We had more goodies than anything around for another ten years. I loved it.

My only concern is that a fairly cheap backup to the helmet might let the jet get on to operational status faster and cheaper. I also wonder how good the pilots will be when the helmet goes tango uniform and the pilot is basically flying steam gauges from 40 years ago.

Gums sends...


You're conflating DAS latency and VHUD frame rate -- not the same. There is no VHUD frame rate issue.
Offline
User avatar

spazsinbad

Elite 5K

Elite 5K

  • Posts: 22854
  • Joined: 05 May 2009, 21:31
  • Location: ɐıןɐɹʇsn∀¯\_(ツ)_/¯
  • Warnings: -2

Unread post31 Oct 2012, 13:06

At the end of long screed 'Gums' says: "...I also wonder how good the pilots will be when the helmet goes tango uniform and the pilot is basically flying steam gauges from 40 years ago." I thought we had covered this dire eventuality if by your sentence you mean 'only the HMDS' is U/S (unserviceable). If HMDS and PCD (Panoramic Cockpit Display) are also u/s at same time then it is time to go home. There is a small separate backup AI display (SFD StandBy Flight Display). Somewhere there must be an backup airspeed display probably on the SFD. What more do you need? :D Power Plus Attitude Equals Performance - right?
________________

Head on over to the recent LM Test Pilot interview regarding the magical HMDS and PCD gizmos.... He's impressed.

Canadian F-35 Aerial Refuelling Considerations (Flying the F-35)

http://www.f-16.net/f-16_forum_viewtopic-t-20548.html
RAN FAA A4G Skyhawk 1970s: https://www.faaaa.asn.au/spazsinbad-a4g/ AND https://www.youtube.com/channel/UCwqC_s6gcCVvG7NOge3qfAQ/
Online

SpudmanWP

Elite 5K

Elite 5K

  • Posts: 8301
  • Joined: 12 Oct 2006, 19:18
  • Location: California

Unread post31 Oct 2012, 16:00

STANDBY FLIGHT DISPLAY
-- 3 ATI Indicator
-- 480x480 Pixel Resolution
-- High Intensity LED Backlight
-- Integrated Switch Bezel
-- NVIS Compatible

Image
"The early bird gets the worm but the second mouse gets the cheese."
Offline
User avatar

spazsinbad

Elite 5K

Elite 5K

  • Posts: 22854
  • Joined: 05 May 2009, 21:31
  • Location: ɐıןɐɹʇsn∀¯\_(ツ)_/¯
  • Warnings: -2

Unread post31 Oct 2012, 20:08

Thanks SWP, looks like everything is there: http://driven-technologies.com/prod_pic ... 35_sfd.png
Attachments
F-35SFDzoom.gif
Last edited by spazsinbad on 31 Oct 2012, 20:09, edited 1 time in total.
RAN FAA A4G Skyhawk 1970s: https://www.faaaa.asn.au/spazsinbad-a4g/ AND https://www.youtube.com/channel/UCwqC_s6gcCVvG7NOge3qfAQ/
Offline

Prinz_Eugn

Forum Veteran

Forum Veteran

  • Posts: 952
  • Joined: 03 Aug 2008, 03:35

Unread post31 Oct 2012, 20:09

480x480 sounds absurdly low to me but I guess that's all you need...
"A visitor from Mars could easily pick out the civilized nations. They have the best implements of war."
Offline
User avatar

spazsinbad

Elite 5K

Elite 5K

  • Posts: 22854
  • Joined: 05 May 2009, 21:31
  • Location: ɐıןɐɹʇsn∀¯\_(ツ)_/¯
  • Warnings: -2

Unread post31 Oct 2012, 20:26

I'll attempt to find more info about the EFI Electronic Flight Instrument (full colour). A bajillion examples of various for the use of EFISs here:

http://www.scribd.com/doc/6948520/EFIS (PDF 9.3Mb)
__________________________________________

F-35A--OPERATIONS PROCEDURES 07 June 2012
AIR FORCE INSTRUCTION 11-2F-35A, VOLUME 3

http://www.e-publishing.af.mil/shared/m ... -35AV3.pdf (0.5Mb)

"INSTRUMENT PROCEDURES
4.1. Display of Endorsed Primary Flight Reference.


4.1.1. Anytime flight conditions (illumination, visibility, weather) or procedures (National Airspace System) require flight by reference to instruments, the pilot MUST select and continuously display an endorsed primary flight reference (PFR). The Standby Flight Display (SFD) and Helmet Mounted Display are not endorsed PFRs. Currently approved single medium PFR displays are heads-down, either:

4.1.1.1. Helmet Mounted Display Virtual Heads-Up Display (HMD v-HUD). Note that under some flight regimes, the horizon line and pitch ladder collides (coexists) with the airspeed, altitude and heading symbology, causing potential readability issues; or,

4.1.1.2. Full-color Electronic Flight Instrument (EFI). When using this display, pilots are prohibited from using the pop-up data entry keypad overlaid on the EFI.

4.1.2. The primary unusual attitude reference is the HMD v-HUD. Do not use the HMD or SFD to recover from an unusual attitude or when executing lost wingman procedures except when no other attitude reference is available."
RAN FAA A4G Skyhawk 1970s: https://www.faaaa.asn.au/spazsinbad-a4g/ AND https://www.youtube.com/channel/UCwqC_s6gcCVvG7NOge3qfAQ/
Offline
User avatar

spazsinbad

Elite 5K

Elite 5K

  • Posts: 22854
  • Joined: 05 May 2009, 21:31
  • Location: ɐıןɐɹʇsn∀¯\_(ツ)_/¯
  • Warnings: -2

Unread post31 Oct 2012, 22:16

F-35 PCD and Graphics Processor info [LAAD Large Area Avionics Display]

Get the 'LAAD(2011)_LR.pdf' 0.5Mb PDF - PCD graphic from this PDF
&'ICP(2011)_LR.pdf' (0.3Mb) from menu at:

http://www2.l-3com.com/displays/product ... s_a-z.html
______________

LynuxWorks LynxOS-178 RTOS to Power F-35 Joint Strike Fighter's (JSF) Next-generation Panoramic Cockpit Display System 15 May 2006

http://www.lynuxworks.com/corporate/pre ... isplay.php

"LynuxWorks to provide DO-178B-certifiable ARINC 653 and POSIX-conformant RTOS for safety-critical, multi-role stealth fighter.

LynuxWorks™ Inc. today announced that L-3 Communications Display Systems has chosen its LynxOS®-178 Real-Time Operating System (RTOS) to power a portion of the Panoramic Cockpit Display (PCD) subsystem for the Lockheed Martin F-35 Joint Strike Fighter (JSF) aircraft.

This display system delivers information for all the major functions of the F-35, including flight and sensor displays, communication, radio and navigation systems as well as an identification system which gives the pilot total situational awareness.

The key factors in L-3 Display System's choice of LynuxWorks' RTOS, which is DO-178B certifiable, were its adherence to open standards, its Linux compatibility, the interoperability benefits of a POSIX® API and support for the ARINC 653 specification. In addition, LynuxWorks will deliver an embedded software product with a complete set of artifacts, along with world-class engineering services....

...In an industry where safety, time and cost are essential factors, L-3 Display Systems is leveraging a series of product features and services from LynuxWorks' LynxOS-178, which includes an RTOS that is designed specifically to fulfill the stringent needs of multithread and multiprocess applications in safety-critical systems. Based on open standards, the LynxOS-178 RTOS provides security through virtual machine brick-wall partitions that make it impossible for system events in one partition of the RTOS to interfere with events in another. It's as if each partition were its own separate computer providing the highest levels of robustness...."
Attachments
PCDbyL3.gif
RAN FAA A4G Skyhawk 1970s: https://www.faaaa.asn.au/spazsinbad-a4g/ AND https://www.youtube.com/channel/UCwqC_s6gcCVvG7NOge3qfAQ/
Offline
User avatar

spazsinbad

Elite 5K

Elite 5K

  • Posts: 22854
  • Joined: 05 May 2009, 21:31
  • Location: ɐıןɐɹʇsn∀¯\_(ツ)_/¯
  • Warnings: -2

Unread post31 Oct 2012, 22:50

For context NATOPS advice about HUDs...

NATOPS INSTRUMENT FLIGHT MANUAL 15 Nov 2006 NAVAIR 00-80T-112

http://www.scribd.com/doc/54516351/Nato ... ght-Manual

"CHAPTER 14 - Attitude Instruments
14.1 GENERAL

The primary flight instrument in all naval aircraft is the attitude indicator. It provides the pilot with a substitute for the Earth’s horizon as a reference in instrument flight. The instrument shows a horizontal bar representing the horizon, upon which a miniature aircraft is superimposed. There are graduated scales on the instrument face to indicate angles of bank and pitch. The combined indications provide a constant visual presentation of the flight attitude of the aircraft as to longitudinal, vertical, and horizontal information. Some aircraft installations may have additional information displayed on the instrument, such as heading, glideslope information, turn and bank, and yaw and course deviation. The pilot should refer to the appropriate NATOPS flight manual for detailed operation of a particular system (Figure 14-1).

14.2 HEADS-UP DISPLAY
Heads-Up Displays (HUDs) are electronic instruments with a centralized means of displaying a large amount of information. They can be used for display of attitude, performance, and position depending on the aircraft and its technology. Figure 14-2 shows a typical HUD configuration and some of the terms for its symbology. The pilot should refer to the appropriate NATOPS flight manual for detailed operation of a particular system.

14.2.1 HUD Limitations
HUDs not endorsed as a Primary Flight Reference (PFR) may be integrated into the normal instrument cross-check, but concerns about insidious failures and its use in maintaining attitude awareness and recovering from unusual attitudes preclude its use as a sole-source instrument reference. Improvements in information integrity and failure indications have increased confidence in the reliability of HUDs; however, the combination of symbology and mechanization enabling their use as a sole-source attitude reference has not been incorporated into all HUDs.

14.2.2 Global Orientation
Many HUDs are incapable of providing intuitive global orientation information because of the small sections of space that they represent. Also, because many HUDs provide only a partial picture of the aircraft attitude, a pilot who tries to use the HUD to confirm an unusual attitude may see only a blur of lines and numbers. In a fast-moving environment, the pilot may not be able to differentiate or recognize the difference between the solid climb lines from the identical, but dashed, dive lines in the flightpath scale. Any confusion or delay in initiating proper recovery inputs may make recovery impossible.

WARNING
Unless your HUD is endorsed as a PFR
, do not use it when spatially disoriented, for recovery from an unusual attitude, or during lost wingman situations; use the heads-down display anytime an immediate attitude reference is required. Typically, heads-down displays are inherently easier to use in these situations because of the larger attitude coverage, color asymmetry between the solid ground and sky, and reduced interference from the outside visual scene (glare, optical illusions, etc.).

14.2.3 HUD Field of View
HUD symbology may also obscure objects within the HUD field of view. When nonessential HUD information is displayed or when the HUD brightness level is excessive, the probability of obscuration is dramatically increased. Proper HUD settings (including elimination of non-task-essential information and adjusting the brightness to the proper level) are imperative to prevent potential hazards to safe flight.

14.2.4 Conventional Cross-Check
Pilots should remain proficient in the conventional instrument cross-check for their specific aircraft. Regardless of the type HUD you have, it is important to fly an instrument approach or accomplish a level-off occasionally without using the HUD so you retain your proficiency in the event of a HUD malfunction. Using HUD information incorrectly or at the wrong time can actually increase pilot workload, but timely, proper use of it can help you fly more precise instruments on a routine basis."
Attachments
NATOPSattitudeIndicator.gif
NATOPShud.gif
Last edited by spazsinbad on 31 Oct 2012, 23:00, edited 2 times in total.
RAN FAA A4G Skyhawk 1970s: https://www.faaaa.asn.au/spazsinbad-a4g/ AND https://www.youtube.com/channel/UCwqC_s6gcCVvG7NOge3qfAQ/
Online

SpudmanWP

Elite 5K

Elite 5K

  • Posts: 8301
  • Joined: 12 Oct 2006, 19:18
  • Location: California

Unread post31 Oct 2012, 22:58

One thing to keep in mind is that the panoramic display is actually two pieces of hardware that can act independently (each 8"hx10"w). They each have their own power and data pathways to the ICP.

In other words, you can put a bullet in one and the functions can be moved to the other.
"The early bird gets the worm but the second mouse gets the cheese."
Online

quicksilver

Elite 2K

Elite 2K

  • Posts: 2541
  • Joined: 16 Feb 2011, 01:30

Unread post31 Oct 2012, 23:51

spazsinbad wrote:At the end of long screed 'Gums' says: "...I also wonder how good the pilots will be when the helmet goes tango uniform and the pilot is basically flying steam gauges from 40 years ago." I thought we had covered this dire eventuality if by your sentence you mean 'only the HMDS' is U/S (unserviceable). If HMDS and PCD (Panoramic Cockpit Display) are also u/s at same time then it is time to go home. There is a small separate backup AI display (SFD StandBy Flight Display). Somewhere there must be an backup airspeed display probably on the SFD. What more do you need? :D Power Plus Attitude Equals Performance - right?
________________

Head on over to the recent LM Test Pilot interview regarding the magical HMDS and PCD gizmos.... He's impressed.

Canadian F-35 Aerial Refuelling Considerations (Flying the F-35)

http://www.f-16.net/f-16_forum_viewtopic-t-20548.html


What if a HUD fails during a cat shot? That's never happened before I guess... :wink:

The HMDS, the two halves of the PCD (as Spud points out) and the SFD all have their own independent power and display generation.
Offline
User avatar

spazsinbad

Elite 5K

Elite 5K

  • Posts: 22854
  • Joined: 05 May 2009, 21:31
  • Location: ɐıןɐɹʇsn∀¯\_(ツ)_/¯
  • Warnings: -2

Unread post01 Nov 2012, 00:16

Two 'No HUD approach' stories on this page of this thread: http://www.f-16.net/index.php?name=PNph ... den#215304 Stroll down to btm.

The two links don't work now (aaaahhh the internet) perhaps they can be found again but anyway here is the ALDEN story....

No HUD and counting on the paddles upgrade! I noticed my heads up display began to flicker before eventually kicking off-line by Joe Alden | Approach 08 Jan, 2012?

http://findarticles.com/p/articles/mi_m ... _84090767/

"Four months into our cruise, the USS Theodore Roosevelt and Air Wing 8 team found itself in the steamy Persian Gulf. After three months of combat in Kosovo and Serbia, we were anxious for our crack at Saddam.

Cyclic ops in the Arabian Gulf always have their share of gotchas: slipper seals that fail, aircraft that slide toward the scupper while turning onto cat 4, diverts into Al Jabbar to hang with the Air Force for a day. Everyone had a story of adventure or misadventure.

Starting at VFA-106, fledgling Hornet drivers practice making circus landings. Unfortunately, FCLPs in the Hornet are not challenging unless done in conjunction with circus approaches. Getting off to a good start and putting your velocity vector next to the lens is a snap and usually will get you one OK-wire after another. Even the circus approaches at the beach don't take on the real-world feeling you get when they actually occur in the middle of some faraway ocean.

This flight wasn't supposed to be exciting, a 2 v 2 with the Toms next door, restricted to the E-2-defined bear cave. We flew the standard, cyclic-ops, max-endurance profiles during the runs, then knocked off to check in with marshal. After completing my fence checks, I noticed my heads up display (HUD) began to flicker before eventually kicking off-line. It had happened to me once before during RAG CQ on the JFK. Cycling the HUD on-off switch usually fixed the problem, but not this day.

Still a nugget, I did the smart thing and "fessed" up to my buddy on AUX. I jiggled the HUD, cycled it on and off, played with the intensity, tested it with BIT, but nothing worked. Now was the time to talk to the ultimate troubleshooter, the CATCC rep. He was our XO and could draw the schematics of the Hornet from memory.

Switching to button two to speak with a rep invites fellow aircrew to listen in. Being a new guy, that was in the back of my mind. With the ship between Farsi Island and Iran, there wasn't room for error. Being head down with my displays and going through an IBIT with a small AOB on the standby gyro halfway between mom and Farsi was inviting trouble. I couldn't bear it any more and stopped the BIT. I found myself two miles from the Farsi standoff range and headed directly for it. I went to mil power and pulled away just before nicking the airspace boundary. My equilibrium was whacked at this point. The next thing I thought of was the helicopter crew that flew over Farsi the week before. Upon their arrival, our battle group commander impounded their helicopter and grounded the crew. I had dodged that bullet.

Back to the rep: He asked if I felt comfortable bringing aboard an aircraft without a HUD. I replied, "Yes." Why? Because I knew from experience that a degraded pass in the Hornet often brought a bonus, usually the OK or the upgrade from paddles. I told the rep I would do it.

Checking into marshal and setting up holding was easy with the HUD on my left DDI. After completing the HAIL checklist, I pushed on time and made my descent. I had bull's-eye and needles frequencies dialed in and received them 4.0. I had all the tools to get me the good start we are accustomed to. Needles showed me with the nice up-and-on, and bull's-eye had me the same. Setting the glide slope with the auto throttles eased the workload tremendously. Still, something in the back of my mind was reminding me of flying the ball in the simulator.

After setting the standard 720 fpm rate of descent, with auto throttles engaged, I clicked them off and began manhandling the throttles. My heart began to race. I was telling myself those Tomcat and Prowler guys do it without a Gucci HUD like ours. I wasn't comfortable looking down at the left DDI for everything I needed to fly the approach. I was used to looking through the HUD. When I called the ball, I only saw meatball, lineup and AOA; no VSI. That is where an NFO would come in handy.

I got off to a great start with needles centered on the velocity vector. I transitioned to head-out-of-the-cockpit and added power to get the ball to crest. That didn't happen. The ball began to rise until it screamed to get off the top of the lens. I knew that it was getting ugly, but I remembered that according to our RAG paddles, no-HUD in the Hornet was an emergency. I bought a bolter bigger than anything.

I had plenty of fuel for several more cracks at it. It never crossed my mind to ask for a mode-one approach. That probably would have been too easy. I wouldn't even have had to deal with the problem, but I wanted to prove to myself I could get the OK 3-wire.

"Four Zero Four, airborne," I sadly called, as I made my ascent to angels one point two.

There were no lights anywhere, except for CVN 71 and her aircraft flying around. I knew what I'd done wrong. Hooking in around six miles, I dirtied up and referenced my DDI. Once again, I made it to a great start with a centered ball and blew it off the top.

"Power back on, bolter, bolter, bolter," was the call as I bought my second one.

My heart was beating out of my chest. Now I was thinking to myself that CAG and the skipper were biting their nails as the only lieutenant junior grade in the two Hornet squadrons was flailing around the gulf. Our ready-room bolt was surely hanging over my lonely seat, suspended from the ceiling by a steel-fishing leader. I came around for the third time and did the same thing. It was getting ugly. I had one pass left before I would either hit the tanker or head to Kuwait. Mustering what little brainpower I had left, I visualized what the pass should look like and went over it again and again on downwind. Getting to a good start was easy; it was flying the ball that was slapping me around. This was it, I was coming aboard.

"Four Zero Four, on and on, three-quarters of a mile, call the ball," I said.

After the ball call, it was my turn to troll. I was coming aboard. So what did I do? I kept leading the low, breaking one of the five LSO rules-to-live-by. Well, I led the low all the way to the ace.

"Welcome aboard," was probably resounding around the ship. It was good to be home. Heading down to the ready room, I couldn't pick up my head. I had just flown four ugly passes in a row. I reassured myself that the Hornet-no-HUD emergency would get the bolters no-counted and the ace auto-no-grade brought up to at least a fair. When I saw the CAG paddles walk into our ready room, I could tell by his look that I was sadly mistaken. After all, he was a Prowler guy, and they do it all the time.

I took it in the face, but it was my own fault. By the way, that shiny bolt was hanging over my ready-room chair as expected. My Ops O showed me his own four-bolter entry in his log book from when he was a J.O. I learned even the best have had their night in the barrel. He had my three bolters and one no-grade beat but not by much.

Starting back in CQ, I should have done more no-HUD and other circus passes in the FCLP pattern. Thinking the no-HUD emergency would buy me the paddles upgrade was ludicrous. My concentration was about half of what it should have been. Thinking about the auto OK was the wrong thing to do. Almost flying over Farsi Island could have been avoided with better aviating and navigating. Trolling the low to get aboard could have been fatal.

What could I have done? Flying the ball to touchdown would have been nice for a start. Applying the LSO rules-to-live-by would have helped as well. Furthermore, this all could have been avoided with a mode-one approach. It was a learning experience and one that could be avoided in the future by preparing and focusing. There are those who have and those who will.

Lt. Alden flies with VFA-87."
Last edited by spazsinbad on 02 Nov 2012, 03:18, edited 3 times in total.
RAN FAA A4G Skyhawk 1970s: https://www.faaaa.asn.au/spazsinbad-a4g/ AND https://www.youtube.com/channel/UCwqC_s6gcCVvG7NOge3qfAQ/
Offline
User avatar

spazsinbad

Elite 5K

Elite 5K

  • Posts: 22854
  • Joined: 05 May 2009, 21:31
  • Location: ɐıןɐɹʇsn∀¯\_(ツ)_/¯
  • Warnings: -2

Unread post01 Nov 2012, 00:41

The other 'HUD fails on Catapult' story....

No-HUD nugget - head up display - troubleshooting instead of flying by Dan Cochran Approach March, 2003

http:/ findarticles.com/p/articles/mi_m0FKE/is_3_48/ai_100172332/

“Blue water in the South China Sea—last launch of the night, and the ship was steaming in a driving rainstorm. The cloud bottoms started at 2,000 feet, and there were layers upon layers through FL300; it was very dark. I was one month out of the RAG, and only four days had passed since our last liberty port. Aside from my day-to-go-night sortie earlier in the day, it had been two weeks since I’d flown.

As I ducked through the hatch leading to the flight deck, my first thought was, “They’re gonna make me fly in this?” It was dark, and the flight deck was slippery. I thought my most dangerous task of the night would be getting to my Hornet, which was parked farthest up the bow. My flashlight did not help much, as I kept my head down to keep the rain from my eyes.

After a cursory preflight, the PC opened the canopy long enough for me to get in the cockpit, but, in the time it took to jump into the jet, the consoles and instruments got soaked from the downpour. I dried off the displays and continued with the launch. The deck was slick, but I managed to taxi to the catapult. As a part of my ever-solidifying habit patterns, I went through my emergency-catapult-flyaway procedure.

I went into tension, wiped out the controls, and made sure I hadn’t popped any flight-control codes. Once assured the jet was ready to fly, I brought up my ADI (gyro) on the right display, flipped the pinkie switch on the outboard throttle, and waited for the cat stroke that would send me hurtling into the black void at the end of the angle deck.

As I felt the reassuring acceleration of the stroke, my HUD blanked out. I instinctively checked my engine instruments, knowing if they were good, I shouldn’t have a problem getting away from the water. My scan went to my right display and the ADI. I rotated to 10 degrees on the ADI and concentrated on keeping my wings level while climbing. It was a few seconds before I remembered to scan the HUD symbology on my left display, and I continued my departure climb.

It wasn’t until passing 10,000 feet, and still in the goo, that I radioed my lead to tell him I had lost my HUD on the cat shot and couldn’t get it back. I was so preoccupied with troubleshoot- ing I neglected to fly the jet. It wasn’t until passing through 25 degrees nose high, with airspeed rapidly dropping, that I focused on the priority task of aviating. I reevaluated my plan of action, and decided to fly my jet, to get out of the clouds, and then to worry about getting back my HUD.

I broke out and my lead— the CAG operations officer— and I joined at 33,000 feet, trying to stay out of the rising clouds. We broke out the PCLs and started to troubleshoot the problem. Our good crew coordination was a plus. It was all I could do to fly formation and not get vertigo. I concentrated on staying in position, as my lead read the PCL and talked me through recovering my HUD—no success. What now?

We agreed I should penetrate the weather on my lead’s wing and have him drop me off on the ball. We started down, and the bright stars quickly were obscured as we descended into the weather. My thoughts went to my last simulator flight in the RAG, which was my emergency carrier-landing hop. I had to fly the no-HUD approach three times because I almost hit the ship on my first two attempts.

At 1,200 feet and eight miles from the ship, we configured for landing. There were no AOA indications in my cockpit. The gear showed three down and locked, and I had an E bracket on my left display but no red chevron. I checked to see if the AOA lights were burned out and discovered I had neither a fast or slow chevron, but the amber donut worked. I told paddles of the possible AOA failure.

At a mile and a half, I saw the lights of the ship appear out the corner of my eye. Lead did a nice job, dropping me off with a centered-ball start, and I transitioned from flying form to flying a good pass. I felt good about the pass until, suddenly, the waveoff lights illuminated, and I heard paddles’ frustrated call, “Wave off, foul deck.”

As I climbed away from the carrier, I spied my flight lead in perfect position at my 10 o’clock. I still had fuel for two more looks before I would have to visit the tanker. We flew around the bolter pattern. Again, at three-quarters of a mile, I transitioned from form flying to ball flying. The transition was too much for me; somewhere in the middle, the ball crept off the top of the lens.

My correction wasn’t enough, and I had to call clara as the ball went off the top of the lens. The LSOs told me to make an easy correction and to keep it coming. My correction wasn’t too easy, and I slammed down before the 1-wire with AB fully engaged. My head flew forward, and it felt like I was riding my nosewheel down the deck as I felt all four wires pass beneath me. I was airborne again! My heart sank as I realized, even after that horrible pass, I had to bring it around for another attempt.

After assuring the tower my hook was down, I decided I needed to fly the pattern myself, so my lead turned downwind without me. Practicing my new scan during the circle around the boat turned out to be the right call. It took me a minute or so to cool down and to get it back together. We were blue-water ops, and I didn’t want to do anymore no-HUD passes.

For the third pass, I was on my own. Although I was turned in early, I still got a good start, which gave me confidence. I concentrated on keeping a better energy package and got aboard without as much terror as the prior pass.

I never was happier to get out of a jet in one piece. I learned a lot that night. All aviators are taught to aviate, navigate, communicate, and to prioritize tasks. Despite looking at the display after my HUD failed on the cat stroke, I did get safely airborne. However, rather than continue to fly away from the water on a black night, I elected to troubleshoot. Fortunately, I wound up in a 25-degree, nose-up attitude, rather than the other direction. The result could have been a lot different.

The other lesson learned focused on crew coordination. My experienced lead did a super job flying me to good starts and being in position to pick me up after two trips down the groove. The formation flying proved to be disorienting for me. I had flown parade to the start and made a disoriented scan transition without the benefit of my primary flight instrument, as I discovered on my third pass. However, it was far easier to practice my degraded instrument scan all the way around the pattern to the start. From there, it was much easier to transition my scan of meatball, lineup, and angle of attack.

Lt. Cochran flies with VFA-195”
Last edited by spazsinbad on 02 Nov 2012, 03:12, edited 2 times in total.
RAN FAA A4G Skyhawk 1970s: https://www.faaaa.asn.au/spazsinbad-a4g/ AND https://www.youtube.com/channel/UCwqC_s6gcCVvG7NOge3qfAQ/
Offline

velocityvector

Active Member

Active Member

  • Posts: 171
  • Joined: 25 Apr 2009, 04:21
  • Location: Chicago

Unread post01 Nov 2012, 01:04

spazsinbad wrote:I got off to a great start with needles centered on the velocity vector.

Happy to assist and as it should be. Not a fan of needles though. Needle squeamishness is one reason why I went digital GA.
PreviousNext

Return to F-35 Avionics

Who is online

Users browsing this forum: No registered users and 2 guests