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  • zraver
    replied
    opsec questions are not allowed.

    Leave a comment:


  • ArtyEngineer
    replied
    Originally posted by Porsche917LH View Post
    Hypothetical here: You lose all control surfaces. (who knows why) as an A10 driver and are at a typical attack altitude flying inverted in a slow roll. Are you screwed?
    .
    Not necessarily, both the ACESII and the latest Martin Baker seats can eject inverted down to as low as 200ft. No idea how they achieve this as it obviously involves reorienting the seat and giving a boost to gain altitude. Got to be one heck of a ride.

    Regards

    Arty

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  • Stitch
    replied
    Originally posted by Porsche917LH View Post
    Wow. Was that where the drone whacked into the mothership?
    I can actually answer this one (finally!): yes, it was the last launch of a D-21 drone from an M-21 "mothership" at M3.5. The D-21 porpoised at release, and took out one of the vertical stabs on the M-21. As you can imagine, instability set in rather quickly, and both the pilot and the LSO elected to eject. Both survived the ejection at M3.5 and 80K but, as zraver mentioned, the LSO drowned after landing in the ocean. After that, Clarence "Kelly" Johnson cancelled all further D-21/M-21 drone flights, and all futher D-21 launches were made from modified B-52's.

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  • Porsche917LH
    replied
    Wow. Was that where the drone whacked into the mothership?

    Hypothetical here: You lose all control surfaces. (who knows why) as an A10 driver and are at a typical attack altitude flying inverted in a slow roll. Are you screwed?

    Oh yeah: When do you guys prefer being called a driver vs. a pilot. Kind of confuses me.

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  • zraver
    replied
    Originally posted by Chogy View Post
    To clarify this a bit, even with a good zero-zero seat, the initial vector of the seat + man system must be taken into account. An aircraft in a 40 degree dive at 500 knots will enter a zone where an ejection will not be successful somewhere in the first 1,000' above the ground. Part of ejection training is to arrest this downward vector before pulling the handle; otherwise, all bets are off. But at the core of it, it is true, a good zero-zero seat would allow you to eject from a parked aircraft and walk away.

    Flail injuries are another matter. High-speed ejections are extremely dangerous, almost guaranteed to produce severe injuries.

    Interestingly, I have a sister-in-law who worked for years on egress systems for the U.S. Navy. She said that Soviet/Russian seats are significantly better/safer than Western seats like the ACES II and Martin-Baker.
    The current Russian seats have a sheild that pops up. Although the US does hold the speed record for ejection- mach 3.5 at 80,000' from a M-21. One of the crew survived, one drowned on landing.

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  • Chogy
    replied
    As long as the seat is not aimed at the ground anyway.
    To clarify this a bit, even with a good zero-zero seat, the initial vector of the seat + man system must be taken into account. An aircraft in a 40 degree dive at 500 knots will enter a zone where an ejection will not be successful somewhere in the first 1,000' above the ground. Part of ejection training is to arrest this downward vector before pulling the handle; otherwise, all bets are off. But at the core of it, it is true, a good zero-zero seat would allow you to eject from a parked aircraft and walk away.

    Flail injuries are another matter. High-speed ejections are extremely dangerous, almost guaranteed to produce severe injuries.

    Interestingly, I have a sister-in-law who worked for years on egress systems for the U.S. Navy. She said that Soviet/Russian seats are significantly better/safer than Western seats like the ACES II and Martin-Baker.

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  • zraver
    replied
    Originally posted by Porsche917LH View Post
    Subject: Ejection seats

    What conditions are necessary for one of you guys to attempt punching out. Altitude, attitude, airspeed etc.
    zero-zero seats can do it sitting on the ground at a dead stop.

    YouTube - A-7 Corsair Brake Failure and Zero-Zero Ejection

    YouTube - Early zero zero ejection seat

    YouTube - ACES II ejection seat test

    As long as the seat is not aimed at the ground anyway.

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  • Porsche917LH
    replied
    Subject: Ejection seats

    What conditions are necessary for one of you guys to attempt punching out. Altitude, attitude, airspeed etc.

    Leave a comment:


  • Chogy
    replied
    Originally posted by Porsche917LH View Post
    Subject fighters: Can A2A missiles ever be employed against ground targets with some effectiveness?
    We often wondered about this! The main problems would be the warhead and fusing.

    An AIM-9 will easily track a decent IR source, regardless of target velocity. A diesel exhaust from a tank or truck is more than adequate, and the missile would likely guide with no problems so long as the background isn't too hot. With the missile enroute, the next step is fusing. A-A fuses are contact and proximity, and there is no way to select/deselect one. As the missile approaches, its prox fuse will likely be triggered by mother Earth too early to be effective against anything even moderately armored. Thin-skinned vehicles or radar might take acceptable damage, though.

    The warhead is optimized for the flying fuel tanks that are airplanes. They deliver large volumes of pyrophoric debris at high velocity, but nothing remotely that might be considered lethal to armor. So you might trash a truck or car, definitely would trash a radar (if you have a heat source to track), but real armor would probably remain unharmed.

    AIM-7/AIM-120 - same fusing problems, same warhead problems, but more importantly, no doppler signal. Anything on the ground would be seen as a rock, a tree, and couldn't be tracked to begin with. There is some potential to track RF signals, but that is the realm of HARM and similar.

    Subject tiltrotors: Do you ever see tiltrotors supplanting helos and or the ac130 in slow CAS?
    This is outside my expertise, but I would have to say no. Tiltrotors combine helicopter and fixed wing functionality, but we already have superb platforms for both when it comes to delivering ordnance. I cannot imagine an Osprey ever coming close to the performance of either an A-10/AC-130, or an Apache, and its unique mechanism makes it a bit more vulnerable than any of the traditional attack assets.

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  • S2
    replied
    scorefour Reply

    "...Is this really so or am I missing something?"

    Perhaps but, unless missiles are shooting at other SAM missiles, isn't it more important what would be our likely targets? If their aircraft are the likely targets of our SAMs, what do they have that defeats our current SAM capabilities?

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  • scorefour
    replied
    SAM's

    With the Russian S-300, S-400, and now the S-500, it seems that the US is lagging badly in this area. Is this really so or am I missing something?

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  • Porsche917LH
    replied
    Subject fighters: Can A2A missiles ever be employed against ground targets with some effectiveness?
    Subject tiltrotors: Do you ever see tiltrotors supplanting helos and or the ac130 in slow CAS?

    Leave a comment:


  • Chogy
    replied
    Originally posted by Ararat View Post
    How does the defender judge when to increasing the closure rate (force an overshoot) while maintaing the break turn.
    The first step is obviously a hard break turn with the lift vector in the attacker's plane of motion. While in the break turn, one must watch the attacker and analyze his maneuvering, which is very difficult when under 8 to 9 G. Primarily, you analyze his nose position relative to your own jet. If he is simply pulling lead (you see the bottom of his jet; he is cutting across the turn circle) then you know he is going for a snap shot to a separation. The closure you create is going to be high, he will be unable to match your line of sight, and when he is in gun range, as the defender, you must change your plane of motion a bit to spoil the shot. Then, get ready to reverse, because he is definitely going to overshoot.

    If he repositions to lag, you will see the reposition, and then see the top of his jet... his nose is not in lead, and any gunfire would be hopelessly behind you. For the moment, he is not a threat.

    The decision to reverse is based upon closure (he is getting big, fast), the line of sight across your six to the outside of the turn, and most importantly, the range behind you that he crosses your flight path. If he crosses closely at a high line of sight, then a reversal will probably work. Too far back, and your reversal will simply solve all his problems for him. A poor reversal decision is common and results in a lost fight. Even a well-executed reversal usually results in some form of scissoring fight. In general, it is better to not reverse when in doubt... keep the turn on, keep the lift vector into him, and drive him hopelessly into lag. Once he's stagnated there, you can then work the vertical with some impunity, increase the angles, and separate, or perhaps force a neutral fight.

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  • Ararat
    replied
    Originally posted by Chogy View Post
    You are welcome, FWIW. It can be dry stuff at times, and with it comes a lot of odd terminology.
    I find it fascinating. I am glad you take the time to share this.....most won't even bother.

    Defender tools are angle-off and closure
    How does the defender judge when to increasing the closure rate (force an overshoot) while maintaing the break turn.

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  • Chogy
    replied
    Originally posted by Ararat View Post
    Do you get accurate altitude/airspeed/range information (with no radar lock) on bandit during such engagements and can it be used to help you judge your closure rate of 50 to 150 knots other than visual?
    You are welcome, FWIW. It can be dry stuff at times, and with it comes a lot of odd terminology.

    Defender tools are angle-off and closure, and if an attacker is not experienced, the defender can and will turn the tables. Every single beginner (without exception) at "Fight's on" doesn't know what to do, and will always simply point at the target, and wonder why he is getting so big, so fast, before scooting through his 6 at high speed. So we discuss canned maneuvers, demonstrate with hands and sticks, demo it in the air, then let them try. It still takes about a year to get a new guy up to any decent proficiency.

    Radars have their auto-acquisition modes which do work very well, and it is rare not to have a lock, but the antenna can be gimballed or otherwise the lock can drop. The eyes tell much. When the bandit turn rate is extraordinarily high, he is cashing in his chips. When moderate, he is sustaining energy. When very low, he is either unaware of you, or inept. The Golden Rule is "maneuver in relation to the bandit" which means rote maneuvers don't always work, and you must analyze (project into the future) his energy, his nose position, and deal with those.

    With all this said, modern all-aspect ordnance, and helmet-mounted sights are definitely changing the game, making any sort of sustained turning very risky. That, and the fact that people don't fly alone. One must assume that there are unseen bandits in the vicinity.

    In Korea, the jets flew around with a 1,500 foot vulnerability bubble. Anything outside of that wasn't much of a threat. In Vietnam, it expanded to several miles. Now, one must deal with a bubble as large as 30+ NM. It's getting scary out there!

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