0
$\begingroup$

What exactly is the sequence of events that would unfold as an F-16 attempts to exceed its service ceiling? The scenario is simply full afterburner and attempting to simply climb higher and higher (at arbitrary/ideal angle of climb) until something prevents that.

I'm curious mostly as how this relates to flight simulators which simulate the F-16, if this can be improved, and if flight simulators already accurately depict what actually would happen in reality.

I'm aware of What determines the maximum altitude a plane can reach? but this is too general and doesn't answer for any specific aircraft. I think it would be both interesting and useful to have a specific aircraft as an example.

What fails first? Engine, or lift? Both more or less simultaneously?

1: What happens to the engine? Will it see an increase in temperature? Will it flame out?

2: What happens to the control surfaces? The airframe? I would imagine nothing, certainly no shaking as portrayed in certain TV series involving aircraft.

3: What happens to the instrumentation? Master caution? Relating to 1, engine warning light? FTIT?

4: Life support, can the life support cope with this?

Improve this question
$\endgroup$
4
  • $\begingroup$ The F-15C has a service ceiling of 65,000 feet, but it also holds an altitude record of nearly 103,000 feet. $\endgroup$
    – Ron Beyer
    Jun 24, 2020 at 21:07
  • $\begingroup$ @Ron, the record-breaking Streak Eagle is not the same aircraft as F-15C (F-15A in fact, and substantially modified). And neither hold the current record. Altitude still belongs to (a version of) MiG-25 (~123K feet). That one actually lost both engines at the apex. $\endgroup$
    – Zeus
    Jun 25, 2020 at 0:41
  • 1
    $\begingroup$ It's not clear whether you are talking about sustained theoretical ceiling, or the highest achievable dynamic ceiling. Either way, this is not a "simply full afterburner" scenario. I don't know F-16 enough to answer, but only in the second case your question becomes interesting: there you indeed may hit the limits of engine (flame-out) and life support, in addition to lift (which by definition will be exceeded: ideally, the aircraft will have zero speed at the apex; in practice it can be <50 kt IAS). $\endgroup$
    – Zeus
    Jun 25, 2020 at 1:29
  • $\begingroup$ What makes you think that the F-16 has a specified service ceiling? I'm not sure you understand what service ceiling is. Service ceiling is a term with a meaning dependent on specific certification criteria. What is the prescribed value by which the service ceiling would be defined for an F-16? $\endgroup$
    – J W
    Jun 26, 2020 at 2:08

1 Answer 1

Reset to default
4
$\begingroup$

What happens in real life is not completely different from what happens in hard sims; the ceiling is not a hard line, but an equilibrium point defined by performance limits.

You can zoom climb well above the static ceiling in a ballistic arc. The static ceiling is simply the point above which the aircraft won't be able to produce enough thrust and lift to sustain that altitude. You'll start losing velocity, and as you do so, also start losing altitude. Nothing fails outright. You just don't have enough energy to climb or even stay level.

The engine will work (but flameout is possible).
The control surfaces will work (but not very well).
The instrumentation will work and there's no master caution for simply exceeding the envelope.
Life support systems will work just fine.

You'll lose altitude whatever you do, however.

Improve this answer
$\endgroup$
4
  • $\begingroup$ You won't necessarily lose altitude, service ceiling is defined as to which you can't climb at more than 100ft/min. What does happen is you get closer and closer to the coffin corner, which is the aerodynamic ceiling. $\endgroup$
    – Ron Beyer
    Jun 24, 2020 at 21:22
  • 1
    $\begingroup$ @RonBeyer coffin corner isn't really relevant to a supersonic aircraft, there are somewhat analogous limits but the behavior is different $\endgroup$
    – pericynthion
    Jun 24, 2020 at 22:11
  • $\begingroup$ You seem to assume that one starts off the service celing and just attempts to climb further. This is not how the highest altitude is achieved. But even if we do that, it's a big question whether we run out of thrust or lift first. Different aircraft have it differently, and I can only guess about F-16. (My guess is lift, but supersonic arcraft often have two local altitude maxima on their envelope). $\endgroup$
    – Zeus
    Jun 25, 2020 at 1:10
  • $\begingroup$ ...If we assume ballistic ('zoom') climb to the dynamic ceiling (it's not clear whether the OP asked about it), then things can be very complicated, and I will argue that most sims will likely have it wrong (particularly with respect to engine behaviour). $\endgroup$
    – Zeus
    Jun 25, 2020 at 1:19

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .