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Are there any fixed wing aircraft that will not exceed Vne if they are taken to their ceiling, engine is pulled to idle or shut down, and then the nose is pointed straight down? Lets assume they are going to pull out of this dive to level flight above sea level without overloading the airframe, which clearly limits the time/distance of the vertical dive.

Are there any aircraft that would not exceed their Vne (and engine speed limits!) in the same scenario as above, but with the engine controls at full power?

If there are aircraft where this is true, are they military fighter aircraft, or are there other (surprising) examples of civilian aircraft where this is true?

This question comes from the realization that aerobatics (and spins, and things like spatial disorientation) can lead to an attitudes with the nose pitched quite down, and in that attitude speed builds quite quickly in many aircraft to speeds above Va, which means pulling out of the dive could easily overstess the airframe. At the same time, not pulling out could also cross Vne and probably continue to increase through any design margin to where the airframe is also overstressed by "forward" (downward) airspeed. Which got me to wondering "are there 1-2 person aerobatic training aircraft out there where this is just not a concern, because the airframe is strong enough and has so much drag?"

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    $\begingroup$ OK. Added an edit. Though I'm OK with the answer being "yes, but only supersonic military aircraft such as the F##". $\endgroup$
    – Azendale
    Commented Sep 20, 2023 at 17:11
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    $\begingroup$ The only aircraft I'm aware of that are Vne limited are gliders with "speed limiting" dive brakes. You can't exceed Vne with them fully extended in any attitude. $\endgroup$
    – John K
    Commented Sep 20, 2023 at 18:18
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    $\begingroup$ @JohnK I've heard the same about gliders, although I've never been brave enough to test. Always seems crazy to me that those little slats out there are so draggy (and strong) that the entire airplane can hang off of them. $\endgroup$
    – Kenn Sebesta
    Commented Sep 21, 2023 at 12:48
  • $\begingroup$ Did we ever get an answer here, leaving out the "full power" part, other than gliders with speed brakes deployed, and dive bombers with speed brakes deployed? How about a Stearman at idle power? How a Pitts at idle power? Just wondering... $\endgroup$
    – quiet flyer
    Commented Sep 28, 2023 at 8:04
  • $\begingroup$ @quietflyer I haven't accepted any answers yet because I really am hoping for answers that talk about the Stearman, Pitts, and fighter planes. $\endgroup$
    – Azendale
    Commented Sep 28, 2023 at 14:21

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Dive bombers, such as the Ju-87 and SBD Dauntless have purpose built dive brakes.

Aircraft designed with an emphasis low drag for fuel economy, such as airliners, are susceptible to rapid airspeed increase when put into a dive.

Extending flaps and spoilers can help control airspeed, but they too are limited to a maximum speed for safe deployment.

Biplanes are very popular for aerobatic flying because they are very strong and draggy.

So, there are 2 critical factors in dive recovery, airspeed and G force limits of the aircraft$^1$, and a third, proximity to earth.

$^1$ also of the pilot

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    $\begingroup$ aside from dive brakes, for propeller planes, there's the braking action of a prop disc windmilling at fine pitch that can reduce terminal velocity $\endgroup$
    – user21228
    Commented Sep 23, 2023 at 6:17

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