How-To fly a Diamond Roll?

"How To" by our Pilot Staff
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lqcorsa
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How-To fly a Diamond Roll?

Post by lqcorsa » Tue Aug 29, 2006 11:35 am

I was wondering if somebody could help me out here. Me and a buddy of mine have started to fly at 13:00 every day for a couple hours training in demo/airshow type of flying. We use a F-15, but as me and him have noticed, the narrow plane makes it hard to look way over and see the itty bitty aircraft and watch the ground and sky ect. at the same time. VTB will be installed today :P . To the point, we need help with the diamond roll. We usually start the roll at about 450 kts with military power on, we pitch nose up attitude to 10 degrees and start our roll. By the we banked 90 degrees were already at about 5 degrees nose down attitude, and we have to use rudder to bring up our angle of attack. When its over, were extremely low to the ground. Can we get some tips on how to execute a precise diamond roll please?
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Burner
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Post by Burner » Tue Aug 29, 2006 11:47 am

Start between 350-400knts. Pitch up to 15 degrees, call the roll as you continue to pitch up this will delay the actual roll to about 20 degrees nose up. As you pass the 90 degree point ease forward with your pull to 'float' the nose. Stop the roll by slowly bringing down the roll rate while simultaneously increasing pull until level.
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Lawndart
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Post by Lawndart » Tue Aug 29, 2006 12:41 pm

Did a quick search of the forums...

Albeit an old procedure, still works and describes the roll in great detail:
http://www.virtualthunderbirds.com/foru ... .php?t=232

Summary of controls required by each wingman:
http://www.virtualthunderbirds.com/foru ... .php?t=585

In a nutshell:

Leading
  • 320-370 knots
  • 88-89% N1
  • Gradual nose up to 15 degrees
  • Initiate roll and top out pitch about 20 degrees nose high
  • Gradual initiation of roll by Lead (no rudder any time!!!)
  • Ease off the backpressure smoothly "Into the Float"
  • Apex with the VV and inverted at the same time
  • Start decreasing roll rate around 235-270 degrees of roll
  • 270-315 degrees in start "Back in with the Pull"
  • Finish roll at same altitude and airspeed as you started
For wingmen
  • Use the control inputs and power changes as necessary to maintain "paint" as described in the link above.
Btw, what did you mean with "...the narrow plane makes it hard to look way over and see the itty bitty"? Not sure I understand.

Also, your AoA (or Angle of Attack) is not desired to bring up. What you are referring to as bringing up is simply the Pitch Angle of the nose (specifically that of the Boss). As a rule of thumb, rudder should only be used for optical reasons and situations requiring speedy lateral movements when changing formation! The Boss should keep his feet on the floor from wheels up til wheels down. AoA has to do with airplane stalls and the angle between the relative wind (path of travel through the air) and the chord line of the wing. At unloaded flight (i.e. the Boss during a roll "Into the Float") and at 300+ knots, stalling is not a concern and neither is AoA. Just to clarify any previous misunderstandings!


[Edit: Added above paragraph]
Last edited by Lawndart on Sun Jan 28, 2007 10:44 am, edited 4 times in total.
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lqcorsa
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Post by lqcorsa » Tue Aug 29, 2006 1:09 pm

LD,

I'm used to aircraft that have wingspans, that travel a little more outward, rather that backwards. Notice how on a F-15, the wings resemble a triangle rather than a T shape, that I'm more familier with? I find it harder to look for visual spots to conectrate on, and even though the F-15 does have a larger wingspan than the F/A-18 that I'm familer with, its wings do seem to cause you to have to look over a little more on a formation. Maybe it's just my opinion, maybe it's not. I prefer aircraft in formations where the wings are a little closer to the corner of my canopy so I can look at everything at the same time. Either way. Thanks for all the info. I'm about to try all that our right now.
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Lawndart
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Post by Lawndart » Tue Jan 09, 2007 8:28 pm

To answer an old thread and provide some more info: Our sight pictures have been updated since and can be viewed in our image gallery @ http://gallery.virtualthunderbirds.com

The textural descriptions (or captions) are helpful in getting the correct alignment of "paint". One limitation of sorts in Lock-On is the lack of peripheral, but regardless, the real pilots never look forward or at their HUD (at all!) while in formation. It's "paint" 100%! What happens in Lock-On is that you need to be far enough forward in a wing position (regardless of aircraft) that you lose sight of your entire HUD (on most monitors incl. widescreens) and essentially the horizon too. The Boss becomes your new horizon and you simply line up (at least two) aircraft parts on the paint or structure of his jet and fly those continuously no matter what the Boss does with his plane.

What it boils down to is that regardless of aircraft type, to fly a proper position, two or more pieces of the Leader's airplane must be positioned from the pilot's point of view (you), until they line up. This establishes a "set" of Up/Down and Fore/Aft positioning and then the spacing is later determined and flown along this theoretical line of sight between ones eyes and the correct "paint".

Needless to say each aircraft and airplane type have various "sets" based on the plane itself, its purpose and tactical use in the formation as well as desired appearance (last one for air shows mostly).

Hope this helps!
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