New Flight Control Improves F-35C Handling Carrier Approach

Unread postPosted: 25 Jul 2012, 21:45
by spazsinbad
New Flight Control Mode Improves F-35C Handling on Landing Approach 25 July 2012 by Tamir Eshel
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+ VIDEO:
F-35 New Flight Control Software
http://www.youtube.com/watch?v=jlqRo3oB ... r_embedded

"Published on Jul 24, 2012 by NAVAIRSYSCOM
A F-35 Joint Strike Fighter test pilot discusses new flight control software
to aid in carrier approaches. Video courtesy of Lockheed Martin."
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http://defense-update.com/20120725_new- ... g-approach

"Flying approaches for a carrier landing just might be a little easier in the future. The F-35 Integrated Test Force at Patuxent River completed the first dedicated test flight May 4 to evaluate the F-35C Lightning II Joint Strike Fighter’s approach handling characteristics with new flight control laws. Part of software version 2A the new flight control software, called Integrated Direct Lift Control (IDLC), translates pilot commands into choreographed changes to engine power and control surface movement, greatly improving glide path control, according to one test pilot....

...Pilots typically qualify to land on a carrier by completing around 30 landings while in initial flight training and at their fleet replacement squadrons. “We have to spend a significant amount of training time on carrier landings, especially night landings,” Bibeau said. “To make all the little high-pressure adjustments takes headwork, intellect and reflexes. It’s unforgiving.” But with the new flight control software IDLC in the F-35, Taylor sees “the potential to reduce the training burden for new pilots going to the ship.”...

...Another change to the F-35C is the redesigned tail hook. Lockheed Martin is confident the redesigned tailhook will be ready for the planned carrier flight tests currently scheduled for 2014. The original hook did not perform well and casued the aircraft to miss the arresting cable too often."

Best to read the entire article with extra pilot quotes at source - tah. :-) 8)

RE: New Flight Control Improves F-35C Handling Carrier Appro

Unread postPosted: 07 Apr 2013, 09:47
by spazsinbad
F-35C Integrated Direct Lift Control: How It Works 09 Oct 2012 Eric Tegler
IDLC will make carrier approaches easier
"...IDLC’s job is to quickly help the pilot make glide slope adjustments during the carrier approach, Buus explains. It is resident within all three F-35 variants, not just the C model.

“What provides a huge benefit to the pilot is that [IDLC] moves the trailing edge flaps up or down to increase or decrease lift, which gives the airplane a very precise glide path control. It almost feels like a predictive control because it happens so quickly and you can get such effective changes in glide path. The trailing edge flaps are pretty large on the F-35C. For a carrier approach we nominally set them to 15 degrees trailing edge down, which is a half-flap configuration. So there’s room for the flaps to come down and to come up and either increase or decrease lift.”

In essence, one could call IDLC “automatic flap response.” Its effect is to literally “heave” the airplane in the vertical axis, Buus says.

“The F-35C is designed to be an auto-throttle flyer on approach. So the pilot will engage auto-throttles and then he just has to fly glide path and lineup with the stick. When he makes pitch-stick inputs to control the glide slope – if he pulls back on the stick a little – the airplane will respond by lowering the flaps to increase lift. The seat-of-the-pants feel is a lot more in the vertical axis. It actually changes the G-level of the airplane; as the flaps come down, they add lift, increasing G and vice versa.”

The pilot is indirectly flying the flaps with the stick, Buus says. From the cockpit, IDLC gives the F-35C exaggerated throttle/pitch response, the test pilot affirms. “It’s almost immediate. It takes longer to make the correction in legacy airplanes.”

NAVAIR contends that IDLC can potentially shorten the carrier qualification learning curve for new pilots by offering more control during the approach, and Buus agrees.

“The flight control engineers have really done an amazing job. IDLC is just one part of it. It’s an easier airplane to fly behind the ship. The easier the airplane is to fly, the safer it is and the easier to train pilots to fly it well. Over time, I think it will reduce some of the training costs and burden to the Fleet.”

In a few years the F-35C’s flight control system will pair with the Joint Precision Approach and Landing System (JPALS) to enable data-linked approaches controlled from the carrier. IDLC will take relevant incoming data from the flight control computer and aid in making the process that much more precise.

With its larger wing and flaps and control harmony, the F-35C benefits more from IDLC than its sister variants. But they too enjoy more precise approach control with the system, Buus maintains. And he adds that it could be integrated into legacy aircraft such as the F/A-18E/F Super Hornet and EA-18G Growler."

http://www.defensemedianetwork.com/stor ... -it-works/

More or less the whole story here and worthwhile to put this good explanation - complete - here.

RE: New Flight Control Improves F-35C Handling Carrier Appro

Unread postPosted: 07 Apr 2013, 12:53
by count_to_10
I'm thinking that when they finally get around to fully automatic, better-than-human carrier landings, it may change the optimum carrier configuration.

Re: RE: New Flight Control Improves F-35C Handling Carrier A

Unread postPosted: 07 Apr 2013, 20:34
by neurotech
count_to_10 wrote:I'm thinking that when they finally get around to fully automatic, better-than-human carrier landings, it may change the optimum carrier configuration.

One of the ready room stories was about a test pilot who had a "hook skip" during F/A-18 CQ because they hit the divot spot on the carrier deck. Because of automatic (coupled) landings done by F/A-18 tailhooks contacting the same spot on the carrier, it made a small divot on the carrier deck, but was enough to bounce the hook and somehow missed 3 and 4 wires. They inspected the deck and repaired it pretty quick, and checked the tailhook was in spec, but it was kind of a surprise that an experienced pilot boltered while flying a tight ball, on a calm day. If a nugget did that, then they'd be like "yeah right..." but sure enough, it happened.

RE: Re: RE: New Flight Control Improves F-35C Handling Carri

Unread postPosted: 07 Apr 2013, 21:05
by spazsinbad
A classic real story from the A4G/HMAS Melbourne era was the hook skip over 5 wire if the hook tip caught the slight rise in the deck from the aft edge of the aft lift (the no.5 wire straddled the aft part of this lift - no.4 {target wire if all five set} was a few feet before the lift). It happened regularly - with variations if the hook skipped earlier and bounced there, it would skip again. Everyone pooh-poohed this notion (except A4G pilots) whilst inspecting the non-smooth transition from deck to lift edge always brought the claim 'what is the problem?'. Answer: "It is not a smooth transition - there is a slight bump". Oh well, all razor blades in China now.

RE: Re: RE: New Flight Control Improves F-35C Handling Carri

Unread postPosted: 08 Apr 2013, 00:10
by KamenRiderBlade
So is automatic landings / takeoff's preferred in this day and age due to enhanced computer accuracy / consistancy?

RE: Re: RE: New Flight Control Improves F-35C Handling Carri

Unread postPosted: 08 Apr 2013, 00:39
by spazsinbad
In the coming JPALS/F-35C (and other suitable USN aircraft) automatic landings will certainly be more precise. These days with current setup Hornet pilots have to be encouraged to do fully automatic approaches (if otherwise they are not warranted due weather/emergency or other conditions) because these landings do not count apparently. Pilots also need to stay current with fully manual landings in all authorised conditions and semi-automatic (to manual takeover at half a mile or less) to remain current. For example if the pilot knows only automatic landings how does he land manually after a long spell with no manual landing practice? Also current completely automatic landings can be quite uncomfortable if the carrier is moving around a lot; but whatever; when needed the auto landings are a boon to tired long flight night return naval aviators. Search the forum for tall tales and true on these points. There was a fairly recent thread about all of this.

For example JPALS and JPALS equipped aircraft especially the F-35C will be able to target a particular wire. This may be important due weather conditions or state of the wires if unserviceable with only one available for example. I guess the USN needs a minimum of two wires out of four to be safe but it all depends I guess what the minimums might be if there is no alternative. If no wires and no BINGO field then a barrier engagement may be an option but this can be hazardous for some aircraft (depending). The F-35C will be tested at Lakehurst going into the CVN barrier at some point.

RE: Re: RE: New Flight Control Improves F-35C Handling Carri

Unread postPosted: 08 Apr 2013, 01:33
by count_to_10
Eventually, an auto landing system should be able to compensate for the motion of the ship. Conceivably, you could end up with a sort of revers catapult system that precisely catches the aircraft coming in at a very high angle of attack on hardpoints, rather than landing gear.

RE: Re: RE: New Flight Control Improves F-35C Handling Carri

Unread postPosted: 08 Apr 2013, 02:11
by spazsinbad
The JPALS does that to some extent especially when used with the BEDFORD ARRAY which will be in use on CVFs for F-35B SRVLs and potentially on CVNs for conventional landings (LSOs think it may be a good idea) early days though. Again search for 'Bedford' for some results here about this.

Re: New Flight Control Improves F-35C Handling Carrier Appro

Unread postPosted: 08 Apr 2013, 13:52
by batu731
Great video and article. F-35 have so much more computational power than legacy fighters, its basically a flying super computer, therefore things like this come naturally.

Re: RE: Re: RE: New Flight Control Improves F-35C Handling C

Unread postPosted: 08 Apr 2013, 14:55
by sferrin
count_to_10 wrote:Eventually, an auto landing system should be able to compensate for the motion of the ship. Conceivably, you could end up with a sort of revers catapult system that precisely catches the aircraft coming in at a very high angle of attack on hardpoints, rather than landing gear.


Never happen.

Re: RE: Re: RE: New Flight Control Improves F-35C Handling C

Unread postPosted: 08 Apr 2013, 18:57
by firstimpulse
sferrin wrote:
count_to_10 wrote:Eventually, an auto landing system should be able to compensate for the motion of the ship. Conceivably, you could end up with a sort of revers catapult system that precisely catches the aircraft coming in at a very high angle of attack on hardpoints, rather than landing gear.


Never happen.


Any reasoning behind that?...

Re: RE: Re: RE: New Flight Control Improves F-35C Handling C

Unread postPosted: 08 Apr 2013, 19:03
by sferrin
firstimpulse wrote:
sferrin wrote:
count_to_10 wrote:Eventually, an auto landing system should be able to compensate for the motion of the ship. Conceivably, you could end up with a sort of revers catapult system that precisely catches the aircraft coming in at a very high angle of attack on hardpoints, rather than landing gear.


Never happen.


Any reasoning behind that?...


You mean aside from the obvious issues?

Re: RE: Re: RE: New Flight Control Improves F-35C Handling C

Unread postPosted: 08 Apr 2013, 20:27
by firstimpulse
sferrin wrote:You mean aside from the obvious issues?


Well, they aren't too obivious to some of us... :oops:

RE: Re: RE: Re: RE: New Flight Control Improves F-35C Handli

Unread postPosted: 08 Apr 2013, 20:44
by spazsinbad
I'll assume that the 'high angle of attack' aircraft slotting into 'hardpoints' will be almost hovering (in the WOD) or will this aircraft be able to land with only aircraft carrier provided WOD (nil wind otherwise). If this approach landing is completely automatic then the pilot will have to be drugged somehow. :D OR will he be able to see through the aircraft to see/monitor the approach OR will an onboard instrument/HMDS III provide said view? I guess 'count_to_10' has the NASA F-16 high angle of attack research (or future similar?) aircraft in mind?

I think I would prefer the skycrane approach - hovering under it to be picked up by the sky hook to be deposited on deck. Some more explanation from 'count_to_10' about his idea would be nice.

RE: Re: RE: Re: RE: New Flight Control Improves F-35C Handli

Unread postPosted: 08 Apr 2013, 20:45
by spazsinbad
double post from extended delay

RE: Re: RE: Re: RE: New Flight Control Improves F-35C Handli

Unread postPosted: 08 Apr 2013, 20:52
by velocityvector
Kind sir, would your suggestion be sky hook or similar on zeppelin or dirigible, or both. I cannot determine. Thanks in advance.

M Go Blue! Defeat Louisville. Please, for the love of god.

RE: Re: RE: Re: RE: New Flight Control Improves F-35C Handli

Unread postPosted: 08 Apr 2013, 20:59
by spazsinbad
Without Googlin' ("Keep on Googlin'" would be a great comeback song for Creedence Clearwater Revival (CCR) or at least an advertisement song for Google by just adapting "Keep on Chooglin' Chooglin' Chooglin'" - but I digress) :D I would have to imagine in my mind's eye a long forgotten photo of those hapless USN Sparrows? hookin' on underneath a giant dirigible. However what I had in mind was the SKYhook as seen in a 'spitballin'' picture for the Brit Harrier to be downloaded with such a device. I believe this forum has a pic from a thread about these issues. So it is a SKYcrane on the ship with a SKYhook that retrieves the wunderairvehickle.

Here is the thread:

F-35B (Non-US) Pocket Carriers

http://www.f-16.net/index.php?name=PNph ... k&start=90

Adapted for shipboard use & new flugelboid:

Image

RE: Re: RE: Re: RE: New Flight Control Improves F-35C Handli

Unread postPosted: 08 Apr 2013, 21:10
by spazsinbad
Here is the shortest version of the Googlin' song (you won't be able to get it out of your heads now :D )

CCR- Keep on Chooglin'

http://www.youtube.com/watch?v=eB8CMN-jX_g

RE: Re: RE: Re: RE: New Flight Control Improves F-35C Handli

Unread postPosted: 08 Apr 2013, 21:12
by velocityvector

RE: Re: RE: Re: RE: New Flight Control Improves F-35C Handli

Unread postPosted: 08 Apr 2013, 21:18
by spazsinbad
Note the problematic 'arm out the window'. Will the new Fluglin' Birdie have a wind down winda? :D

RE: Re: RE: Re: RE: New Flight Control Improves F-35C Handli

Unread postPosted: 08 Apr 2013, 21:25
by spazsinbad
Chooglin' "freedom" on this forum I came across this link with some 'autoland stories' or links to same: http://www.f-16.net/index.php?name=PNph ... dom#247556 particularly "Couple Up for Safety" by USN LSOs about ACLS Mode 1 approaches etc.

By the bye let us hope that if the F-35 can be 'fogged out' that the HMDS II does not 'fog up' as well. Then that completely automatic landing WILL come in handy.

Re: RE: Re: RE: Re: RE: New Flight Control Improves F-35C Ha

Unread postPosted: 08 Apr 2013, 22:09
by count_to_10
spazsinbad wrote:I'll assume that the 'high angle of attack' aircraft slotting into 'hardpoints' will be almost hovering (in the WOD) or will this aircraft be able to land with only aircraft carrier provided WOD (nil wind otherwise). If this approach landing is completely automatic then the pilot will have to be drugged somehow. :D OR will he be able to see through the aircraft to see/monitor the approach OR will an onboard instrument/HMDS III provide said view? I guess 'count_to_10' has the NASA F-16 high angle of attack research (or future similar?) aircraft in mind?

I think I would prefer the skycrane approach - hovering under it to be picked up by the sky hook to be deposited on deck. Some more explanation from 'count_to_10' about his idea would be nice.

No, I was thinking more of like a catcher's mitt of sorts. Something that would lock on to purpose built hardpoints on the aircraft as it is doing a very slow, high angle of attack approach behind the ship, and then slow the aircraft the rest of the way down to the velocity of the ship. For take-off, you would use the same system to catapult the aircraft at a similarly high angle up above the ship (or perhaps at an angle). That way, you would not longer need a "flattop" or "through-deck" to operate jets.
I'm not sure how fast the aircraft would have to come in -- presumably above it's stall speed, but a jet with T2W of above unity and TVC could presumably get down to anything it wanted to. The important part is that you don't have to come in level, and you might be able to actually flair to a stall.
I'm also mostly imagining UAVs here, but there is no reason it couldn't be done with a manned aircraft automatically. Just tell the pilot to suck it up and push the "land" button.

RE: Re: RE: Re: RE: Re: RE: New Flight Control Improves F-35

Unread postPosted: 08 Apr 2013, 22:23
by spazsinbad
I guess the robot driver is going to 'flare to stall' and the pilot will automatically eject? :D Catcher's mitt huh. Will it have to be broken in like a human one? So this High Angle of Attack approach at the end will result in a hover more or less in the WOD? What is different from a vertical landing? Perhaps a smidgeon of forward groundspeed into the Mitt (will they call it a Romney approach?). Seems to me that a VL is more doable because it is being duntoday. No?

Re: RE: Re: RE: Re: RE: Re: RE: New Flight Control Improves

Unread postPosted: 09 Apr 2013, 00:54
by neurotech
spazsinbad wrote:I guess the robot driver is going to 'flare to stall' and the pilot will automatically eject? :D Catcher's mitt huh. Will it have to be broken in like a human one? So this High Angle of Attack approach at the end will result in a hover more or less in the WOD? What is different from a vertical landing? Perhaps a smidgeon of forward groundspeed into the Mitt (will they call it a Romney approach?). Seems to me that a VL is more doable because it is being duntoday. No?

They have barricade nets on carriers to stop aircraft that are unable to trap. I'm guessing with a Short Rolling Vertical Landing, a barricade engagement becomes an option if they come in too fast.

RE: Re: RE: Re: RE: Re: RE: Re: RE: New Flight Control Impro

Unread postPosted: 09 Apr 2013, 01:28
by spazsinbad
'neurotech' said: "...I'm guessing with a Short Rolling Vertical Landing, a barricade engagement becomes an option if they come in too fast." I see no sign of that at moment on CVFs (CVNs OK). A barricade engagement is not like a pre-wedding variety. Sure the damage may be minimised if barricade engagement optimal but it would be for an emergency (and no sign of any installation on CVFs). The barricade uses an arresting gear engine OR there may be another method for a non-arresting engine CVF barricade (maybe that is where the velvet glove catcher mitt comes in?). :D

I'll wager that if an SRVL is viable on CVF that no barricade will be required. IF there is a 'no brake' emergency then VL. If that means jettison valuable stores then so be it; rather than risk some kind of non-existent barricade SRVL on CVF. Perhaps if a CVN nearby the UK or USMC or whomever F-35B could SRVL trundle into a barricade. I can hear the pen pushers now.

I wonder if a trial barricade arrest by an F-35B in various configurations at NAS Lakehurst will be trialled?

Unread postPosted: 09 Apr 2013, 02:22
by popcorn
Maybe the smart guys at DARPA can figure something out for their TERN initiative. How to recover a Predator-sized UAV onto a LCS or frigate. A giant batcher's mitt made from aerogel perhaps..
https://www.aviationweek.com/Blogs.aspx ... 32ce68c8fa :)

Re: RE: Re: RE: Re: RE: Re: RE: New Flight Control Improves

Unread postPosted: 09 Apr 2013, 02:49
by count_to_10
spazsinbad wrote:I guess the robot driver is going to 'flare to stall' and the pilot will automatically eject? :D Catcher's mitt huh. Will it have to be broken in like a human one? So this High Angle of Attack approach at the end will result in a hover more or less in the WOD? What is different from a vertical landing? Perhaps a smidgeon of forward groundspeed into the Mitt (will they call it a Romney approach?). Seems to me that a VL is more doable because it is being duntoday. No?

Vertical landings require a lot of extra weight and volume. What I'm talking about would be a way of offloading the landing gear to the ship, and could be done for aircraft with lower thrust to weight.

RE: Re: RE: Re: RE: Re: RE: Re: RE: New Flight Control Impro

Unread postPosted: 09 Apr 2013, 03:05
by spazsinbad
How much does the landing gear and associated equipment weigh? What about landing ashore? Sounds like the 'rubber deck' problem from the beginning of the jet age in the RN with a Sea Vampire driven by Winkle Brown bumping along the rubber deck sans wheels. It did not fly. No one bothered to figure out how to land ashore perhaps catapulting from a trolley (ala jet unmanned Jindivik remote controlled target doing a runway takeoff & landing back on a skid on a conventional runway) was OK but then....

Re: RE: Re: RE: Re: RE: Re: RE: Re: RE: New Flight Control I

Unread postPosted: 09 Apr 2013, 05:32
by neurotech
spazsinbad wrote:How much does the landing gear and associated equipment weigh? What about landing ashore? Sounds like the 'rubber deck' problem from the beginning of the jet age in the RN with a Sea Vampire driven by Winkle Brown bumping along the rubber deck sans wheels. It did not fly. No one bothered to figure out how to land ashore perhaps catapulting from a trolley (ala jet unmanned Jindivik remote controlled target doing a runway takeoff & landing back on a skid on a conventional runway) was OK but then....

Not much. Pilots have crash landed after ripping off the landing gear, and the weight reduction is minimal.

I actually think the F-35 lift-fan is optimal.

Part of the reason why the X-32 was designed ended up the way it did was because Boeing were directed to use a F119 engine, and adding a bypass turbofan would have been difficult without redesigning the engine.

RE: Re: RE: Re: RE: Re: RE: Re: RE: Re: RE: New Flight Contr

Unread postPosted: 09 Apr 2013, 07:38
by spazsinbad
'neurotech' said above: "...Not much. Pilots have crash landed after ripping off the landing gear, and the weight reduction is minimal...." Exactly the weight loss is minimal - however the possibility of damage during a no undercarriage landing is not minimal. It all depends on the design of the aircraft. Many aircraft in the past (I'm thinking of the MIRACLE Mirage IIIO were not allowed a no U/C landing. So every landing ashore requires a maintenance cycle? Seems to be a silly proposition all round.

Re: RE: Re: RE: Re: RE: Re: RE: Re: RE: Re: RE: New Flight C

Unread postPosted: 09 Apr 2013, 09:01
by neurotech
spazsinbad wrote:'neurotech' said above: "...Not much. Pilots have crash landed after ripping off the landing gear, and the weight reduction is minimal...." Exactly the weight loss is minimal - however the possibility of damage during a no undercarriage landing is not minimal. It all depends on the design of the aircraft. Many aircraft in the past (I'm thinking of the MIRACLE Mirage IIIO were not allowed a no U/C landing. So every landing ashore requires a maintenance cycle? Seems to be a silly proposition all round.

That was partly me being funny. A 767 did a successful belly up landing but totaled the jet. A 777 at Heathrow landed short and ripped the main gear off, totaled as well. I remember an experienced Mirage pilot said the no U/C procedure is;
Step 1) Eject! Eject!
Step 2) There is no step 2.
After a pilot or two successfully landed, probably on a center drop tank, they changed the procedures to allow an emergency landing.

RE: Re: RE: Re: RE: Re: RE: Re: RE: Re: RE: Re: RE: New Flig

Unread postPosted: 09 Apr 2013, 09:57
by spazsinbad
'neurotech' I have outlined the 'unintentional' underwing drop tank Miracle landing earlier - at Tullamarine - which changed the RAAFieCHAPpy minds about 'Miracles landing on empty drop tanks' earlier. I don't know if it was ever done again - don't think so. I'll find the link here - hmmm - perhaps info mentioned not here, so I'll post the info soonish

Here 'tis: http://www.f-16.net/index.php?name=PNph ... iio#236812