Behaviour on Aircraft Damage

[ZeroAlpha]

What is the correct behaviour for AI on aircraft taking damage?

Situation

H-6 takes two AMRAAM hits. No loss of speed or altitude, proceeds for >100NM and launches a full salvo of cruise missiles.

What are the odds (dice roll) of neither hits causing damage to engine or control surfaces?

I would expect that after the first lot of engine damage, top speed would be reduced, fuel burn on remaining engines would increase as power compensated. For any subsequent engine loss or damage, altitude and speed would typically be impacted ana routine to calculate the need to jettison payload would occur.

Thoughts?

[Dimitris]

What does the enemy's message log say?

[ZeroAlpha]

Multiple runs of the same scenario (last scenario in Chains of War). Have looked at logs, and it appears:

* Unusually high number of misses from high-probability (greater than 70% pH)
* Cumulative damage doesn't trigger jettison of stores (most recently, single engine damage, aircraft damage approx 72%, stores not dumped

I guess to understand if this is WAD or not, it would be useful to understand the relationship between structural integrity and sub-system damage. Should structural integrity degradation force stores to be dumped? i.e ESM/HF/DECM goes from damaged to destroyed by a second missile hit, this would normally be associated with aircraft taking fragmentation damage and taking out modules. But should those modules be capable of being damaged without surrounding structure being chopped up?

[Dimitris]

Hi,

Can you post a save prior to the AMRAAM impacts ? Cheers.

[Dimitris]

Bump

[Dimitris]

bump

[ZeroAlpha]

Uploaded

Looks like some aircraft are returning to base, but without load jettison.

[ZeroAlpha]

Bump

[Siegen]

I've had the same problem on this scenario. Each AMRAAM or Sparrow hit does at most 25% damage to the H-6 bomber. The number of misses also seems improbable given the Pks listed in the message log.

[Dimitris]

Just had a look at this.

The H-6M has a DP value of 20. The AIM-120D has a frag warhead with a DP value of 5. This means that, not taking into account checks for critical hits on cockpit/fuselage/engines, it will take 4 direct hits to bring down a H-6M.

AMRAAM is designed primarily as an anti-fighter weapon and its warhead is suited to this task (an F-16A has 5 DPs so a direct hit will bring it down instantly; even a much more durable fighter like the F-15E [10DP] will immediately take 50% damage, which will force it to immediately abort). It is not well-suited to engaging larger air targets as this example demonstrates, unless a lucky subsystem hit is achieved.

For comparison, the R-33 has a 14DP warhead (it is designed expressly to disable/destroy bombers) so a direct hit by that missile will immediately force the bomber to abort, if it's not destroyed by enveloping fire or systems damage first.

Which of the above is unreasonable?

[Dimitris]

BTW, I checked the message log for any clues as to the strange behavior that you are describing (carrying on to mission even with heavy damage) and did not find anything.

[Dimitris]

ORIGINAL: Siegen
I've had the same problem on this scenario. Each AMRAAM or Sparrow hit does at most 25% damage to the H-6 bomber. The number of misses also seems improbable given the Pks listed in the message log.

Please follow the process. New thread, save file for investigation, etc. Thanks.

[c3k]

I'm not very experienced at playing CMANO, but I am an aviator. I find it very hard to believe that an H-6M bomber can absorb an AMRAAM hit and continue with its mission. I understand the DP system, to a degree. However, aircraft have many vulnerabilities short of structural failure. Holes in the wings induce fuel leaks: hard to continue (assuming no fire!) without fuel. Hydraulic lines, aerodynamics (especially from peeled back sections), flight controls, generators, crew, oxygen, etc. Most frequently, a hit to an engine causes shredded turbine blades. They'll tend to rip apart the engine, any nearby engine, and any part of the aircraft in the plane of rotation. Best radar return is either the radome or engine face (from a face-on aspect). Either location is deadly if hit by an AMRAAM, even if the rest of the aircraft is "okay".

I'm sure you've studied this before you arrived at the conclusion that a modernized Tu-16 could take 3 AMRAAMs and continue the mission. I'd love to see some real-world test data supporting this level of robustness.

(But, hey, I -do- love the game. )

[Dimitris]

ORIGINAL: c3k

I'm not very experienced at playing CMANO, but I am an aviator. I find it very hard to believe that an H-6M bomber can absorb an AMRAAM hit and continue with its mission. I understand the DP system, to a degree. However, aircraft have many vulnerabilities short of structural failure. Holes in the wings induce fuel leaks: hard to continue (assuming no fire!) without fuel. Hydraulic lines, aerodynamics (especially from peeled back sections), flight controls, generators, crew, oxygen, etc. Most frequently, a hit to an engine causes shredded turbine blades. They'll tend to rip apart the engine, any nearby engine, and any part of the aircraft in the plane of rotation. Best radar return is either the radome or engine face (from a face-on aspect). Either location is deadly if hit by an AMRAAM, even if the rest of the aircraft is "okay".

I'm sure you've studied this before you arrived at the conclusion that a modernized Tu-16 could take 3 AMRAAMs and continue the mission. I'd love to see some real-world test data supporting this level of robustness.

(But, hey, I -do- love the game. )

Thanks. Notice that I did add the caveat "not taking into account checks for critical hits on cockpit/fuselage/engines". So the "4 hits to take down" assumes no hits on engines, fuselage or cockpit at all, which is unlikely.

One of the modifiers we have for the probabilities to hit these subsystems is the aircraft size. Basically the larger the airframe gets, the less likely it is that the weapon will impact at/near these systems.

For example, the nominal probability of hitting the cockpit is as follows:
Small AC: 40%
Medium AC: 30%
Large AC: 20%
Very Large AC: 10%

This is further modified by the aspect of the incoming impact. If the weapon is hitting on the frontal quarter, the probability is multiplied by 1.5.

So in the example of the H-6M (very large AC), the probability of a missile impacting close enough to the cockpit to evaluate for penetration is 10% * 1.5 = 15%. The reasoning being that there is simply so much other volume/area of the aircraft that weapon may happen to near-detonate instead.

Based on your description, I understand you feel that such a figure is an underestimation.

Perhaps a further modifier would need to be applied, based on the guidance type of the weapon? (E.g. radar-guided missiles coming from the front have an increased probability of going for the cockpit and engine intakes, whereas IR missiles and radar-aimed gun rounds have a more equal distribution because they have no hot point). This could potentially over-complicate things.

Or is your objection more towards secondary damage? (We already have a high likelihood of fire eruption, and indeed in all the test runs I did both Badgers suffered fire damage throughout their retreat).

Cheers.

[Siegen]

I think my problem is more or less the same as zeroAlpha's so a new thread is not necessary.
To be blunt, I find it highly unlikely that a H-6M could survive multiple AMRAAM hits. I am no expert, but it is doubtful that one could give a definite answer on something like this anyhow.

I don't know of any cases of modern bombers being struck by missiles, but I will illustrate my point by comparing to incidents with similarly sized commercial aircraft. There is a list of such shootdown incidents. (See "List of Airliner Shootdown Incidents" on Wikipedia)
The difference posed by military-specification construction notwithstanding, I think it should provide some food for thought.

First of all, I do not know if the H-6M in particular is pressurized, but there are large military aircraft with pressurized fuselages (eg. the B-52). Given that minuscule cracks from metal fatigue, in the absence of any trigger whatsoever, have been known to cause explosive decompression on commercial aircraft (resulting, more often than not, in mid-air disintegration of the aircraft), I suspect that bombers like the H-6M would suffer explosive decompression if struck on the fuselage at altitude by even a grenade-sized warhead, let alone the fifty pound one on the AMRAAM.

There are cases of airliners being struck by missiles, such as in the case of the downing of an Airbus A300 by an SM-2 (with a warhead similar to that of the AMRAAM's) from the USS Vincennes, which caused the aircraft to explode and disintegrate in midair. There have been a few other similar cases, and I am pretty sure there has never been a case of an airliner struck by an AMRAAM-sized missile surviving. Airliners have survived being hit by smaller missiles, but not without heavy damage. For example, in 2003 an SA-14 MANPAD hit an Airbus A300 on the wingtip, and caused complete loss of flight control. The aircraft managed to land by steering using differential power.

There are also incidents involving mid-air collisions which illustrate how extraordinarily fragile aircraft are.
In the case of Gol Transport Flight 1907, there was a glancing collision between a Boeing 737 and a Embraer Legacy 600 business jet. The business jet landed safely, but the 737 disintegrated in midair. How? The winglet on the business jet sliced the 737's wing off.
In another incident (PSA flight 182) a low speed, low altitude mid-air collision with a Cessna 172 caused a 727 to fall out of the sky in flames.

It is worth noting that 727s are larger than H-6Ms, and that a Cessna 172 weighs about as much as four or five AMRAAMs.

[c3k]

Sunburn,

Thanks for the detailed reply. You are correct: I disagree. The larger an aircraft is, the MORE systems they have (measured in surface area). Proportionality does not matter. An AMRAAM warhead has 40 pounds of explosive. If it detonates near an F16, the fragments have a smaller target to hit than if it detonates at the same distance from an H-6M. The H6M has more plumbing, more engines, more "stuff" which can get hit.

Also, take a look at the images from the Malaysian Airlines shootdown over Ukraine. The cockpit is shredded by explosive fragments. The missile "homed in" on the largest reflector...the weather radar. It doesn't matter if it's emitting or not: that parabolic antenna is a great reflector.

Missiles are aimed at specific parts of an aircraft: radar antenna, engine inlet, engine exhaust, air conditioner exhaust, and, for some of the imaging IR seekers, at the pilot's head. These are not random bullets striking a target.

Just food for thought.

Edited to add: as Siegen, above, stated, aircraft are VERY fragile. However, that is for pressurized (passenger) aircraft. Most (all?) large military aircraft, when given notice, will depressurize prior to entering a combat zone. (Yes, this means "hanging on the hose", using oxygen, if above about 10,000 feet.) It also presupposes warning. AWACS do not depressurize: not "in" a combat zone where they are likely to be hit. C17s on a low-level would be depressurized. (Also, aircraft will turn off their air conditioning to eliminate that hot spot on their fuselage if going into a known enemy zone.)

[Dimitris]

Good points both, thanks. We intend to cover this in multiple phases; the first one is an overview of AAW warhead DP values which is currently underway.

[ZeroAlpha]

ORIGINAL: Sunburn

Good points both, thanks. We intend to cover this in multiple phases; the first one is an overview of AAW warhead DP values which is currently underway.

Great news.

It would also be useful to understand how the warhead type impacts (pun intended) on damage pattern to aircraft. For instance, whether a blast/frag is more likely to cause multiple systems damage to a lower hit value compared to say a penetrating warhead more likely to destroy a single system.

Perhaps it would also be useful looking at aircraft pressurisation condition and how that relates to damage too.

[Dimitris]

We added a number of tweaks to the damage model; these will be included on one of the forthcoming update releases.

[ZeroAlpha]

Awesome work Devs