Modifications Thunderbirds and Blue Angels

Military aircraft - Post cold war aircraft, including for example B-2, Gripen, F-18E/F Super Hornet, Rafale, and Typhoon.
User avatar
Active Member
Active Member
 
Posts: 159
Joined: 30 Nov 2016, 06:30

by rowbeartoe » 12 Sep 2019, 02:07

Hi Everyone.

According to Wikipedia and a website on the upcoming Super Hornet for the Blue Angels only slight modifications are being made to the aircraft. They are as follows.

Current F/A-18.
*Removal of the weapons and replacement with the tank that contains smoke-oil used in demonstrations.
*Control stick spring system for more precise aircraft control input. Control sticks are tensioned with 35 pounds (16 kg) of force installed on the control stick as to allow the pilot minimal room for un-commanded movement.

Future F/A-18 Super Hornet
* Biodegradable colored smoke injectors,
* Fuel flow modifications to facilitate extended inverted flight
* The addition of 7-pounds of forward hydraulic force on the control stick when maintaining level flight to improve the handling of the aircraft in turbulent, close formation flying

F-16C Thunderbird.
* Replacement of the 20 mm cannon and ammunition drum with a smoke-generating system, including its plumbing and control switches
* The removal of the jet fuel starter exhaust door

Control Stick Questions:
F-18's. Why not make the control stick modifications for all military F-18s rather than just the Blue Angels?
F-16's. Why don't they make modifications for the control sticks on the F-16s?
F-18E/F. Why not have the fuel flow modifications as standard just incase you needed extended inverted flight?

Isn't it misleading to "demonstrate" aircraft with control stick modifications that standard aircraft do not have? One thing I always here people say is look how tight the formation is of the Blue Angels over the Thunderbirds and then I have to mention that the Angels have control stick modifications to assist in such maneuvers. This doesn't mean the Thunderbirds cannot perform tighter maneuvers, (an accident I believe influenced the birds to fly less close recently) it just means the Blue Angels made the modifications to make the maneuvers safer than they would otherwise be.

Anyhow. Those are my questions and my 2 cents. Thank you everyone.


User avatar
Elite 1K
Elite 1K
 
Posts: 1393
Joined: 29 Jun 2004, 20:14
Location: Cheyenne WY

by Roscoe » 29 Mar 2020, 07:51

Every stick has what is called "deadband" and/or "breakout" force...deadband is "slop" in the stick at the center point where breakout force is the amount of force required to start movement. Both of these challenge close formation flying when precise stick inputs are required. In UPT, pilots were typically taught to dial in a bit of nose down trim which subsequently forced the pilot to fly with a little back pressure on the stick. This got the stick to of the deadband/breakout region and made precise formation flying much easier.

The F-18 (if I recall what I read somewhere) did not have the ability to force the stick out of the center position with trim. The original trick was to attach a bungee cord from the stick to the instrument panel. This "pulling" of the stick forward forced the pilot to apply aft stick pressure, accomplishing the same as above. I suspect the mod mentioned was a better engineered version of the bungee cord.
Roscoe
F-16 Program Manager
USAF Test Pilot School 92A

"It's time to get medieval, I'm goin' in for guns" - Dos Gringos


Elite 5K
Elite 5K
 
Posts: 5974
Joined: 10 Mar 2006, 01:24
Location: Nashua NH USA

by sprstdlyscottsmn » 29 Mar 2020, 15:59

And the F-16 stick doesn't move
"Spurts"

-Pilot
-Aerospace Engineer
-Army Medic
-FMS Systems Engineer
-PFD Systems Engineer
-PATRIOT Systems Engineer


Senior member
Senior member
 
Posts: 440
Joined: 13 Mar 2019, 00:07

by f119doctor » 29 Mar 2020, 22:01

sprstdlyscottsmn wrote:And the F-16 stick doesn't move


I know that early F-16 sticks were force measuring only, with no movement. But didn’t later F-16 sticks move just a little to give pilots a little more feedback and reduce the “roll ratcheting “ that a lot of pilots experienced when the aircraft roll resulted in less pressure on the stick, which slowed the roll, which increased the pressure, etc....?
P&W FSR (retired) - TF30 / F100 /F119 /F135


Elite 5K
Elite 5K
 
Posts: 5974
Joined: 10 Mar 2006, 01:24
Location: Nashua NH USA

by sprstdlyscottsmn » 30 Mar 2020, 01:56

Correct, but they are still pressure sticks and only move half an inch. No purpose served in modifying them
"Spurts"

-Pilot
-Aerospace Engineer
-Army Medic
-FMS Systems Engineer
-PFD Systems Engineer
-PATRIOT Systems Engineer


Senior member
Senior member
 
Posts: 440
Joined: 13 Mar 2019, 00:07

by f119doctor » 30 Mar 2020, 21:01

sprstdlyscottsmn wrote:Correct, but they are still pressure sticks and only move half an inch. No purpose served in modifying them


True, but I believe you can trim the aircraft so you have to carry some steady pressure on the stick to maintain level flight, which might be advantageous during formation flight.

This was an issue in the YF-22 PIO hard landing event. The engineers couldn’t duplicate the event in the simulator until they dialed in some nose up trim in the landing configuration, which moved the low gain stick “dead band” off center. Turned out all of the YF-22 test pilots were doing this, being more comfortable carrying some nose down pressure on the stick during landing.
P&W FSR (retired) - TF30 / F100 /F119 /F135


Elite 5K
Elite 5K
 
Posts: 5974
Joined: 10 Mar 2006, 01:24
Location: Nashua NH USA

by sprstdlyscottsmn » 30 Mar 2020, 21:20

That would be a user level modification, not an aircraft level modification. I had not heard that about the YF-22 belly flop.
"Spurts"

-Pilot
-Aerospace Engineer
-Army Medic
-FMS Systems Engineer
-PFD Systems Engineer
-PATRIOT Systems Engineer


Active Member
Active Member
 
Posts: 246
Joined: 14 May 2007, 19:46
Location: Southlake, TX and West Yellowstone, MT

by Meteor » 30 Mar 2020, 21:21

rowbeartoe wrote:Hi Everyone.

Control Stick Questions:
F-18's. Why not make the control stick modifications for all military F-18s rather than just the Blue Angels?
F-16's. Why don't they make modifications for the control sticks on the F-16s?
F-18E/F. Why not have the fuel flow modifications as standard just incase you needed extended inverted flight?



Because the aerial demonstration teams fly 95% of their sortie in very close formation where the object is to impress the taxpayers who are watching. Modifying the aircraft to enhance the show make sense.

In the "real world", fighters might spend 1-3 minutes of a sortie in close formation, usually while flying up initial upon RTB. During the rest of the 1-15 hour sortie, the last thing you want is to be having to hold back stick pressure simply to maintain level flight.

In my years of flying the T-37, T-38, F-4, and F-16, I never felt the need to trim out of the dead zone band in order to fly fingertip formation.

(…which may be why I was never a T-bird!)
F-4C/D, F-16A/B/C/D, 727, DC-10, MD-80, A321


Active Member
Active Member
 
Posts: 172
Joined: 05 Aug 2009, 01:31
Location: VA

by jbgator » 31 Mar 2020, 00:03

Having many friends who were Thunderchickens, and instructed a few, I know they run the trim forward to create a constant aft stick pressure requirement for close formation aerobatics. As Meteor said, that's fine for loops to music but not practical for extended operational flying. But in the case of the F-16, all the pilot hand to do was run the trim button forward, no dufus bungee or spring required. My most personal experience was instructing Dana Atkins on his initial checkout in the jet. Dana came from the A-10 but was an exceptional pilot none the less (yeah I guess that's a tongue in cheek jab at Hawg guys). In his course we did one single ship TR ride then a two ship formation. Knowing Dana was going to the Chickens I planned a lot of formation stuff. I demoed some then gave him the jet. He was flailing around some so I took the jet back to demo more and found it was trimmed full nose down. He told me that was how the TBirds flew but I told him he could learn that when he went and flew red, white, and blue jets with no guns in them and proceeded to demo trimmed up formation which I'm sure was close enough for me. Obviously Dana got it, had a great Tbird tour, and went on to be a LTG. If he ever reads this, my hat's off to him. Great job despite the substandard instruction he got in his TR phase.


User avatar
Elite 5K
Elite 5K
 
Posts: 28404
Joined: 05 May 2009, 21:31
Location: Australia

by spazsinbad » 03 Apr 2020, 16:23

'GOUGE' is good if accurate and/or useful so I'll guess every miljet pilot has a lot to share about particular aircraft -however I'll stick to some answers for some of the OP questions mebbe. The attached JPG shows why an Angelic Blue Pilote needs some extra inverted fuel time. Having flown a mirror formation in a MACCHI MB326H with max. 10 seconds of inverted flying time (I was No.2 directly underneath inverted leader at some hundreds of feet) I could have welcomed some Blues gouge about how they orient their formations to the crowd line to give a better impression of their wonderful cozy shenanigans.

Different A4Gs had different wobbly sticks in that some wobbled more around that still point more than others. With a 720 degree per second roll rate at best roll speed of 250 KIAS ALWAYS the first student takeoff had a dramatic roll PIO as they 'wrestled' with the wobbly stick. One learnt to relax and carry on. :-)

One gouge was to have slight nose down trim when flying at 50 feet over water or the reverse OR just have neutral trim.

The worst gouge I found personally was having the seat full down for a night catapult launch. BS indeedy especially if one usually flew with seat as high as possible. I NEARLY DIED. :-) And I only tried it ONCE!
Attachments
BluesDirtyInvertedMirror.jpg


User avatar
Elite 5K
Elite 5K
 
Posts: 28404
Joined: 05 May 2009, 21:31
Location: Australia

by spazsinbad » 03 Apr 2020, 16:37

About the F-16 I have no clue while this fatal Thunderbird accident report is noteworthy for the inverted flight time....
Thunderbirds Pilot Lost Consciousness Before Fatal Crash, Air Force Says
16 Oct 2018 Oriana Pawlyk

"..."During the 'High Bomb Burst Rejoin,' an aerial maneuver near the scheduled end of the aerial demonstration training flight, the [mishap pilot] flew the [mishap aircraft] for approximately 22 seconds in inverted flight between 5,500 and 5,700 feet above ground level," the report states...." [GEASLES & REDeye probably https://fightersweep.com/6322/the-centr ... o-pull-gs/ ]

Source: https://www.military.com/dodbuzz/2018/1 ... -says.html


Senior member
Senior member
 
Posts: 273
Joined: 05 Jan 2007, 22:36
Location: Aust.

by beepa » 02 Mar 2021, 03:06

Probably the wrong thread but have a look at this new Blue Angels air to air video, great stuff. https://youtu.be/WeYYwD067A4


User avatar
Elite 5K
Elite 5K
 
Posts: 28404
Joined: 05 May 2009, 21:31
Location: Australia

by spazsinbad » 02 Mar 2021, 04:59

Aviation Medical article PDF about PUSH-PULL -G +G EFFECT relevant to F-16 Thunderbird Fatal Crash mentioned above.
PUSH PULL: A Medical Perspective
2021 Dr Bob Banks

"PILOTS KNOW ABOUT G in general terms. Pull the stick back and houses get smaller, positive G (+G) increases, blood goes to the feet, vision turns grey (greyout), or tunnels, or even turns black (blackout). If it continues long enough, G-induced loss of consciousness (GLOC) occurs and you rubber chicken. Do the anti-G strain.

On the other hand, push the stick forward and houses get bigger, negative G (-G) increases, blood goes to the head, eyes bugout. Don’t do the strain.

Is that about it? Perhaps, but research has identified something else — the push-pull effect....

...In summary, a problem has been identified regarding +G tolerance: the push-pull effect. Thus, pilots should consider the starting +G, in addition to magnitude of +G, rate-of-onset and time of exposure, when considering their ability to tolerate +G. In addition:

• push-pull effect is worse with more -G

• push-pull effect is worse with longer duration of exposure to -G

• the anti-G strain manoeuvre is at least partially successful in countering the problem, but relaxation during +G may allow push-pull effect to return; and

• tall people may be more susceptible to push-pull effect."

Source: https://www.defence.gov.au/DASP/Docs/Me ... l-2021.pdf (4.3Mb)
Attachments
PUSHpull G Aviation Medical SpotlightSpecial-2021 pp2.pdf
(204.04 KiB) Downloaded 388 times


User avatar
Elite 5K
Elite 5K
 
Posts: 28404
Joined: 05 May 2009, 21:31
Location: Australia

by spazsinbad » 03 Mar 2021, 14:02

JPG attached is a combo of the two JPGs at URLs below (sadly FATSO ALBO missed out).

http://alert5.com/2021/03/03/thunderbir ... more-87216

http://alert5.com/wp-content/uploads/20 ... 539854.jpg (5.2Mb) Supers & Thunders F-16s
&
http://alert5.com/wp-content/uploads/20 ... 539846.jpg (6Mb) PLUS FAT ALBERT (also new - a second hand refurbished C-130J from the RAF)
Attachments
Blues Tbirds Combined TIF.jpg


User avatar
Elite 5K
Elite 5K
 
Posts: 28404
Joined: 05 May 2009, 21:31
Location: Australia

by spazsinbad » 23 Mar 2021, 13:18

BLUES bros Angels with Super Hornets in 17 page PDF at NAF El Centro recently from AIRSPEED magazine April 2021.
Attachments
Blue Angels Super Hornets Airspeed Apr 2021 PRN pp17.pdf
(8.46 MiB) Downloaded 435 times
BluesSupers6deltaElCentro2021.jpg


Next

Who is online
Users browsing this forum: No registered users and 16 guests