The point being made is that if the Sedjil maneuvers in combined plane, and has the maximum maneuverability given to it - the Phoenix likely uses similar guidance and should also be given its’ maximum load limit. It was further evidence that the Phoenix has more than 17G’s maneuvering limits seeing as it was designed with higher wing load limits and deflection angles than the Sedjil.
According to the same document, 20g capability was not integrated into the I-Hawk until 1974, they even tried to reduce manoeuvrability to 12g in 1973.
To the contrary
The document clearly states that the increased 20g and 22 deg AoA limits which were chosen in 1969 due to change in requirements, were the “current I-Hawk” specs at the time of the writing of this report in 1973.
In fact, the whole reason for the very existence of this document is that the 20G 22 deg limits caused some breakups / failures in service. (Which is not relevant to WT as it does not model reliability)
As a result, the Ad Hoc group was consulted to independently investigate the matter and come up with potential causes and solutions.
And limiting the missile to 12G and 15 deg (which are the limits of the Basic HAWK) was only one of the many suggested (temporary) “potential fixes”:
Which is not clear if (this particular fix, limiting the missile to 12G and 15 deg AoA) was even implemented …
A follow on 1974 report makes it clear that the suggested final fix is the incorporation of ERCL (Elevon Rate Command Limiter) with 20G and 26 deg AoA limits.
Which means that the the main reason for the breakups was actually loss of roll control, rather than the 20G pull on the wings, but also noting that the “elevon hinge moment” might possibly be the main cause, “if there is a single cause”:
All in all, the missile went into production and was in service with 20G and 22 deg limits for a few years.
Even if the limits were later temporarily lowered to 12g and 15 deg to increase missile’s reliability and lower the chance of breakup that’s not relevant for WT.
AFAIK, the G limit for F-14 was lowered later in its service to extend the life of the operational airframes as well … That has no relevance in WT …
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It kinda is relevant to WT, since the missile did not work properly when pulling said 20g single plane…
As WT only models single plane maneuverability, the Sedgil should be dropped to 12g single plane, as that was the determined g loading the missile could functionally pull without structural failure.
The missile should be limited to what was determined to be functional irl.
And btw, saying it was “in service” with 20g does not mean it could pull 20g. It means the guidance computer could try to pull 20g, not that the missile could pull 20g. From the documents it seems rather clear that the missile could not pull the full 20g the guidance computer might try to pull, which is why the guidance computer was eventually revised down to 12g.
The limits were increased in 1969 during the development process. (And seems like the missile went into production the same year)
The missile was declared operational in 1971/1972
This report is from 1973
The missile was completely functional with the 20g and 22 deg limits.
It was just later determined that the missile had some reliability problems.
No missile has 100% reliability IRL.
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You’re misunderstanding the whole case.
The missile structurally could not sustain the full commanded 20g’s. What the guidance computer would try to pull is irrelevant, the missile could not do it. It was reduced to prevent it from even trying.
Just because the guidance controller tries to do something, does not mean the missile structure CAN do said thing.
This excerpt you posted literally stated that all missiles that failed had the same issue: they tried to pull too hard and broke up.
No
The missile could sustain 20G
That’s why only a fraction of the launches resulted in loss of control and breakup.
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The fraction of the missiles that failed were all the missiles that had the common element of “terminal high g maneuver”
ie: they pulled to hard and could NOT sustain it
It isnt optimal to always pull max g’s, the missiles that did not fail clearly did not attempt to pull the full 20g single plane.
Your own sources prove clear as day the I-HAWK cannot pull 20G single plane. It is structuraly incapable of doing so
Where does it say that
That’s just on the list of many “potential fixes” suggested by the Ad Hoc group which was consulted to investigate the matter.
BTW, as I explained here, it does not seem like Sedjil was modified as per the suggestions of the Ad Hoc group, as the 1974 follow on report says that the “gapped wing configuration” has solved the elevon hinge moment potential cause of the problem, but Sedjil does not have gapped win configuration:
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You’re right, “potential” reduction to 12g.
Doesnt change the fact that regardless of what change was eventually implemented, the Sedjil is in structural configuration of the I-HAWK that has a guidance computer with a 20g limit, but a structural limit that is very clearly below said level. The missile CANT pull 20g, but it could try (and fail).
Which means more so than anything that the Sedjil CANNOT pull 20g, as no fix for the high g loss of control/breakup was implemented lmao
At the end of the day, its up to gaijin to decide if they will choose to model the missiles max g limits based on the guidance computers theoretical attempted limits, or the missiles very real structural and aerodynamic limits. I’m curious to hear what the decision on that point will be @David_Bowie
The failure is not a guarantee. It has a chance of failure, like all missiles do (be it higher or lower).
It’s not like the missile went into production and service without testing it with the 20g and 22 deg limits.
The report itself makes it clear that the I-Hawk airframe is 20G capable:
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“Terminal high G maneuver” doesn’t mean it tried pulling 20g and broke its wings.
It means the missile completely lost controlled flight (due to loss of roll control) and essentially went sideways.
The report states the wings have a negative factor of safety at 20g single plane commanded
And states “the change may have pushed a marginally safe design into a flight region where loss of control is statistically probable”
ie: Not all would fail, but most would.
“Terminal high G maneuver” means “it pulled a lot of g’s before attempted impact and subsequent failure”
You’re clearly selectively interpreting this document as favourably as you can, and not objectively. The missile was more likely than not to fail if it tried to pull 20g’s. All missiles that DID fail tried to pull a “high g maneuver” This actually doesnt even mean 20g’s btw, 20g’s is just the guidance controllers limit, it is entirely possible and even probable the missiles lost control before even hitting the 20g mark.
Says who
Where did you pull that from?
If you read the 1974 report you will understand that wing overload is not the cause of the problem.
The problem was a control problem …
Hence the suggested 20g & 26 deg AoA limits with the incorporation of ERCL (Elevon rate command limiter) “to fully utilize the IH airframe’s 20g capability”.
Plus, you can see that even with 12g limit the missile was still not 100% reliable (as no missile is):
Thats what “statistically probable” means…
Thats a blatant lie, you’ve once again selectively ignored other portions of the report, and even quoted the sentence wrong.
ERCL is “necessary but not sufficient”
Which is why the part you misquoted says “near-full”, not “full” like you’re pretending it says.
The 20g limit mentioned is likely combined plane btw:
12g ± 2g single plane, 19.8g combined plane with a factor of safety of 30% to account for overshoot
Its possible its meaning 20g single plane, but thats definitly not what I’m understanding to be the actual single plane capability of the missile in the Sedjil’s configuration.
The 20g limit mentioned is likely combined plane btw
Pretty sure MiG_23M already explained that before if you want to scroll up
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I’ve had MiG_23M blocked for months, so I didnt see it. Point still stands the sedgil should not be capable of pulling 20g’s in-game. Tho Sudo_su’s point of “reliability not being a factor in WT” is technically true, if a missile has a statistically significant chance of catastrophic failure when attempting to pull a certain level of G’s, that imo falls out of the realm of a “reliability” issue, and into the “structural/design limits” category.
If a plane could hit M2.8, but had a “statistically significant” chance of blowing up trying to do so, itd be limited to a top speed at which it didnt blow up yanno?
At the end of the day tho, like I siad, thats up to gaijin. Imo the report very much reads as “the I-HAWK (and therefore the sedgil in its current config) cant pull the desired 20g’s (single plane) without a good chance of breaking apart, structural and guidance changes are required to allow it to pull the 20g design limit (combined plane) of the missile”
It was originally designed with 14G in mind, but later in 1969, the target g requirements were raised from 3g to 6g and consequently commanded g and AoA were increased to 20g and 22 deg (which is what the missile went into production and operational service with and stayed until at least 1974.
Then there is this part, (as one of many suggested potential fixes in the initial 1973 report) suggesting limiting “commanded G” to 12, “which is what the structure was designed to accommodate”
And we know that the 12/14G value is the single plane design limit of the wings.
Meaning the missile autopilot actually pulls its (20g) “commanded g” in single plane.
And:
Spoiler
I.e. the autopilot is not capable of dual plane maneuvering, thus it cannot equally distribute the load on both pairs of wings. So:
1- “When pitch and yaw are limited” (e.g. The autopilot is trying to pull 5G in one axis and 10G in another axis), the forces are not “being distributed equally on both sets of wings”.
1- Only when the autopilot is trying to pull max G in both axes (i.e. “When pitch and yaw are not limited”, i.e. When the autopilot is trying to pull 20G in pitch and 20G in yaw), the forces are “being distributed equally on both sets of wings”
You can’t really compare plane reliability with missile reliability.
Now granted, even a lot of planes and tanks had reliability problems and limitations IRL that they don’t have in the game.
But with missiles and bombs, reliability failures are even more common. (especially if we are talking late 1960s and early 1970s)
OK “near-full” …!
Yes, as I said, there were some other modifications as well.
The point was that it was mainly a control problem. And the fact that the 1974 report itself says that I-Hawk’s airframe is 20g capable.
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