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So, in most drafting/modelling software, we have a feature called Snap to Angle or Snap to Edge; its function is to snap the control(cursor) to the nearest most obvious angle/edge to relieve strain on operator to carefully move the cursor to that exact point.
If you haven't seen it try Right Click on Desktop > View > Align Icons to Grid & then move the icons around.

Now on to my question:
When performing the maneuver Opposing Knife Edge it is crucial that the roll angle (w.r.t. level) should be very close to ±90°. enter image description here Especially considering the high speed (& probably high G-Force) situations is a feature equivalent to CAD's Snap-to-Angle employed in air-show modified jets?

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    $\begingroup$ You seem to have a seperate question there at the end, if you could go ahead and put it in another question...that would be preferable. $\endgroup$ – Jay Carr Jun 14 '15 at 5:11
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    $\begingroup$ Think about all the times snap-to doesn't do quite what you want. There's no place for a "feature" like that in a aerobatic fighter cockpit. $\endgroup$ – dimo414 Jun 14 '15 at 7:34
  • $\begingroup$ The closest you will get to this is the Airbus Control Laws I think. $\endgroup$ – Thunderstrike Jun 14 '15 at 14:58
  • $\begingroup$ Along Dimo414's line of thinking, pilots have a preference for being more in control of their aircraft, and are willing to pay a price in convenience. In CAD, you are in charge of a few thousand dollar computer with an undo feature, so having the computer help is actually a really smart assistance feature. In command of a multimillion dollar aircraft with one chance to do any given thing right, the less one is forced to trust the plane's computer, the happier they seem to be. $\endgroup$ – Cort Ammon Jun 14 '15 at 19:38
  • $\begingroup$ In reality, it is not that crucial to have exactly 90° roll for this manoeuvre. 2-3° won't make any visual difference, especially when viewed as on the photo. Meanwhile, any experienced pilot can hold the roll within 1-2°. Speed has little effect here, and G-force is not really great (probably even less than 1). $\endgroup$ – Zeus May 5 '16 at 6:07
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Short answer: No.

Long answer: No way!

This would be a feature which pilots would never accept and for good reasons.
There are many instances where you want to fly at a slight angle to exactly horizontal or vertical to make corrections. Just think of flying an approach with crosswind.

The designers have made the cockpit glazing transparent to enable the pilot to check and adjust his/her attitude, and this feature works really well. There is no need to add something which will be in the way of proper flying at some times.

What you do find sometimes on small aircraft with manual controls, however, is a trailing edge modification which helps with centering the rudder and/or the ailerons. See below for an example: This is the tail of the Klemm 35, and the rudder has two narrow strips which are deflected slightly to the left and the right, respectively. This increases the force gradient over deflection for the first few degrees when the rudder is moved away from its centered position.

Klemm 35 tail detail

Klemm 35 tail detail (own work)

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    $\begingroup$ "The designers have made the cockpit glazing transparent:" a wise choice (although that may change in the future). $\endgroup$ – 2012rcampion Jun 14 '15 at 17:53
  • $\begingroup$ Thanks man and sorry if I provoked anything wrong. Just wish I could enroll in Blue Angels someday . . . $\endgroup$ – RinkyPinku Jun 16 '15 at 22:03
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In addition to Peter's great answer... In the Viper, the stick only moves ~1/4 inch. With this little movement, there's not really room built in to be able to offer this "feature".

Some jets do, however, have different stick characteristics. For example, the first 1/2 of stick movement may be responsible for 3/4 control surface deflection (so it's not linear). Another example may be that the last 1/4 of stick deflection experiences greater force to prevent over Gs or avoid breaking an ops limit.

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  • $\begingroup$ Thanks for the great input. Where can I learn these things? $\endgroup$ – RinkyPinku Jun 16 '15 at 22:05
  • $\begingroup$ What is an ops limit sir? $\endgroup$ – RinkyPinku Aug 6 '15 at 8:29
  • $\begingroup$ ops = operations, as in flight ops = flight operations $\endgroup$ – Burhan Khalid Aug 6 '15 at 9:50
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    $\begingroup$ What is even more important (and fundamentally different from cursor positioning) is that roll is generally controlled via roll rate and not the angle directly. That is, stick deflection is proportional to the angle rate rather than the angle itself. This makes precise positioning much easier. $\endgroup$ – Zeus May 5 '16 at 6:13
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I can't speak for the Blue Angels, but there are some airplanes that have this feature: those equipped with a DFC100 autopilot.

enter image description here

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Its difficult to see how this feature could ever work, because you move the stick to move the wings, and then centralise it again to stop the roll. I am sure though it would never be quite central, small adjustments would have to be made all the time to make the flight path accurate and the aircraft might be overbanking or under banking depending on its attitude for example. So its truly pilot skill you are seeing when you watch the Blues and long may it continue this way!

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  • $\begingroup$ This is what I tried to say in my comment to @TUMBLEWEED. Aircraft is generally controlled by angle rates rather than angles, in roll especially. In a dynamic environment such as a flying aircraft, such first-derivative control was shown to be nearly ideal for humans. That said, there are autopilots/control systems that 'snap' to certain angles or simulate direct angle control in some specific scenarios. $\endgroup$ – Zeus May 5 '16 at 9:23

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