project-navigation
Personal tools

Author Topic: 2 questions on human aircraft designs  (Read 22419 times)

Guildenstern

  • Guest
Re: 2 questions on human aircraft designs
« Reply #15 on: March 31, 2008, 05:15:31 pm »
  I think the main misunderstanding that is going on here about this topic and some of the suggestions I've made is this, I'm working on items for the game as they fit from what I can see of the ufopedia(what has been laid down and released to date).  I feel that your points in particular are valid, realistic projections of future tech, however they serve simply to point out the disjoint between the present story and the current game universe. 
  With all the projected robotic goodies that should be available by the 2080's, not to mention the advances in rocketry we'd hope that man would have A)gotten a base outside the earth-moon system B)shown some major private development in the same department.  When we examine the entries in the game's ufopedia, specifically the 3rd entry in background we find that in the aftermath of the first attack NASA abandons ISS 1 & 2, the moon colony, and scrubs mars missions.  For a world with AI superplanes that is really weak.
  What I have been trying to do this entire post is to get something workable for the game's interception and aircraft design that can either then be implemented by myself or somebody else that would like to take up the quest.  While it would be nice to have something hyper realistic, this would require a semi-major rewrite (which I think has to be done by BTAxis or Winter), and until they change it I will work with what I've got.  So if you'd like to join me in trying to hammer something together that works with the story to date I'd say to jump right in and help, with your research skills you may uncover something very helpful that we could use to be a more futuristic spin on things without bouncing outside the story as it stands now.
  The war angle I suggested earlier went something like this, in the game, the second cold war destroys the US economy, causing utter collapse, I could see this causing a fair amount of damage to the technical output of the US and possible loss of technological advancements during that time.  After this, the other major player in the world stage (China) is rendered apart in a nuclear civil war.  By the game time, 2084 we have our 8 global powers, 4 of which have stated technical outputs, Asia makes holography and nanotech, North America has aerospace, Russia has fusion reactors, and the middle east has pharmacology.  This idea works well if we are talking about the years in the 30's-40's (right after the big civil war) but that extra 50 years is an issue.  Oceania. New Africa, and The revolutionary countries wouldn't be doing much because by the game's account they are catching up to everybody else (Oceania is rebuilding after the nukes fell, New Africa is developing infrastructure, The revolutionary countries are focused on economic development)  The GEU is sitting on its hands during this time supposedly, so those last 50 years we've got 4 major players in the tech game at war with nobody.
  Those are essentially the pieces we've got to put together.  The best I can really come up with is to say that the aircraft we've got (with pilots, run a forum search for the posts if you want) are the end result of nobody really wanting to play war after watching a country exterminate its own people with nuclear weapons.
  As far as dealing with the g-force problem, I think that Knightsubzero was on point.  In theory, one could use the gravitation dilation of time attached to the general theory of relativity to increase the relative time of the people inside the craft.  As the g-force is a function of acceleration which of course is a function of time, that should greatly reduce the force involved.  Total sci-fi stretch and some black-boxing, but anything advanced needs to have a somewhat technical tone to it for the ufopedia article.  A "Well commander, we bolted that doohickey on and our pilots stopped turning to blood jelly on the seat so we left it there" won't work.
  Lets try to work within the constraints of the storyline at the moment to see how we can get something developed to bring the aircraft combat up to snuff.  Its either that or to have the storyline altered to allow a more futuristic outlook on the world in general.
  Hoped that helped to explain what angle I was attacking from (and not just trying to defend my point, if you show me something that works well with "what we've got" I'll be all over it),
  Guildenstern

Serrax

  • Guest
Re: 2 questions on human aircraft designs
« Reply #16 on: March 31, 2008, 08:29:55 pm »
Hi.

As I wrote before, if it is correct that human pilots will be implemented to this game, the discussion about 'projections to the future' has no use. And well, as I can hardly code 'hello world', I'm not so useful in pushing this project foreward.

But even with the official setting, there're still countries with high-tech military industries left, which could develop advanced weapons or systems.

cu

Sophisanmus

  • Guest
Re: 2 questions on human aircraft designs
« Reply #17 on: April 01, 2008, 07:39:54 pm »
Alien ships may well have some form or forms of camouflage or ECM capable of fooling (not necessarily jamming) human-built AI. 

Perhaps alien ships absorb/distort/refract radar randomly; this may allow radar to pick up their general location, but distorts their signature too much to pin down their exact location, let alone allow a radar-dependant AI to track and fire upon them with any accuracy.  A human pilot would be harder to fool with such defenses.

Perhaps alien ships use visual displacement/distortion to hinder any optical-capable human AI.  It would also hamper a human pilot's effectiveness, but a human pilot would be capable of actively observing, testing, and learning the weaknesses in the system. 

Perhaps alien ships use weapons which do not behave like human weaponry, which can be evaded or otherwise circumvented through more creative means, which would not be possible with semi-futuristic AI. 

I would suppose that eventually though the collective experience of veteran human pilots, research into Alien tech, and possibly a computing breakthrough or two, the player could develop an AI which is at least similarly capable to a human pilot at combating the new, alien threat, but even if that is included in the game experienced human pilots would still present the best performance for interception and dogfighting. 

I guess there would be a choice involved: AI (Poor), Human (Competent, achieving Excellence with experience), and late-game Advanced AI (Competent++, minimal/no improvement with experience).

Offline Psawhn

  • Squad Leader
  • ****
  • Posts: 210
    • View Profile
Re: 2 questions on human aircraft designs
« Reply #18 on: April 11, 2008, 10:15:32 pm »
Something to note: current fighter craft are also structurally limited to 9 g. (Less if they have heavy bombs mounted and stuff). Also, aerodynamically, a high speed turn bleeds off a lot of airspeed. Sure, your 'robot' pilot could take 14 g's, but the plane will fall apart after a dozen missions (even with advanced composite materials and the like), and running out of speed could get it shot down just as easily. (The agility of missiles will always exceed that of any fighter craft). It could very well be that the performance advantage of an AI pilot is low enough that the intelligence of an onboard human tactician is worthwhile, especially when fighting an unknown enemy. This especially becomes important when going against antimatter missiles - there's no way that even an advanced antimatter-powered hybrid craft can outmaneuver the missile, so it's better to just go with ECM to try to fool the missile into missing. (Tactical positioning has less importance when your missile can turn around and hit someone behind you.)

In space, combat is even more different. Orbital maneuvering has many, many quirks. I can't really get my head around what orbital combat will look like. (Imagine: Going 'slower' actually reduces your orbit and makes you faster.) Deep space combat is a different beast yet again.

Serrax

  • Guest
Re: 2 questions on human aircraft designs
« Reply #19 on: April 12, 2008, 12:02:07 am »
@Psawhn:

Quote
Something to note: current fighter craft are also structurally limited to 9 g. (Less if they have heavy bombs mounted and stuff). Also, aerodynamically, a high speed turn bleeds off a lot of airspeed. Sure, your 'robot' pilot could take 14 g's, but the plane will fall apart after a dozen missions (even with advanced composite materials and the like), and running out of speed could get it shot down just as easily.
1. The missile AIM-54 Phoenix (for the F14 Tomcat) got in service in 1974. This missile can fly 16 g at a top speed of more than 4,800 kph. G-forces are no problems for AI aircrafts.

2. From the WW2 'ME262' to the 'Eurofighter' or 'F22' today, we had 60 years of development. 60 years and the structure of the aircrafts got several 100% stronger (from maybe 3g to 9g). So, how many g will the aircraft structure stand in another 60 years of development?

3. As for AI pilots, you need no pressurized cabin or live support system - you can build the interceptor smaller and with stronger structure.

4. How many missions against an UFO do you believe is the estimated span of live for an interceptor? In WW1 and WW2 it was clear that the pilots (and the aircrafts) had a very little span of live - often not more than a few weeks or months.
In UFO:AI you don't need an interceptor which is cabable of flying 1,000,000,000,000 km and can stand 1,000,000 landings and takeoffs. I suppose a span of live of maybe 5 missions for every interceptor.

Quote
It could very well be that the performance advantage of an AI pilot is low enough that the intelligence of an onboard human tactician is worthwhile, especially when fighting an unknown enemy
What do you believe that you'll notice at a speed of 5.000 kph? We know from examples of today, that even at 2.000 kph a human is no longer able to react early enough, for example to fire misslies or to drop bombs at a target - or to avoid a crash.
You simply cannot see the target  as your brain and your eyes work not fast enough (in contrast to many animals, btw). In the case of two aircrafts flying towards each other, the sum of the velocities can reach incredibly 10.000 kph. That are 2.7 km per second. Plus you have to add the velocities of the missiles and/or projectiles.

Do you really believe a human pilot can fight under these circumstances? Sorry, but no chance at all!

Quote
This especially becomes important when going against antimatter missiles - there's no way that even an advanced antimatter-powered hybrid craft can outmaneuver the missile, so it's better to just go with ECM to try to fool the missile into missing. (Tactical positioning has less importance when your missile can turn around and hit someone behind you.)
Sorry, but i don't understand your argument.

1. In case you cannot evade an antimatter-propelled missile - why should we risk a pilot?

2. If you assume, that an antimatter-propelled missile would reach extrem velocities - you might be right.

But: The alien technology is not that advanced up to now (2.2). The UFOs are running at a speed, similar to the best human interceptors.

3. I suppose, a missile with extrem speed - antimatter-propelled or not - will simply vaporize in the atmosphere. For example the probe 'Galileo' entering Jupiter's atmosphere (which is far less dense at this point than the Earth's atmosphere) at a speed of 170,000 kph (47 km per second) reached a temperature of 16,000 K. It survived just thanks to its heat shield - which made up 2/3 of the probe's mass. Even worse is the situation if you like to alter the course of the missile - the missile would break and vaporize.

cu
« Last Edit: April 12, 2008, 12:08:19 am by Serrax »

Offline Doctor J

  • Squad Leader
  • ****
  • Posts: 265
    • View Profile
Re: 2 questions on human aircraft designs
« Reply #20 on: April 12, 2008, 05:38:07 am »
Sure, your 'robot' pilot could take 14 g's, but the plane will fall apart after a dozen missions

Currently i can expect that every time a Harvester decides to stop running and engage me, the Stiletto and the Harvester each get destroyed.  As we used to say in the days of the Cold War, MAD [Mutually Assured Destruction].  For the sake of argument, let's say that 50% of launches end up engaging.  Thus, on average, the Stiletto only needs to last two flights.  If the robot plane goes fast enough to force engagement every time, then it only needs to last a single flight. 

[light goes on]  I guess where i'm going with this is an evolution of the Cruise Missile.  I see that India and Russia currently have a cruise missile that approaches Mach 3, and are working on a new version that will do Mach 8.  We have 80 years to improve the range, speed, and onboard intelligence of the missile [currently they have to be given a target coordinate, but the more sophisticated missiles will make a decision to change their angle of attack based on what the onboard camera sees]. 

So it is only when our planes are beefy enough to take the punishment that the UFOs dish out that we have to worry about how long the craft will last.

Offline Psawhn

  • Squad Leader
  • ****
  • Posts: 210
    • View Profile
Re: 2 questions on human aircraft designs
« Reply #21 on: April 22, 2008, 11:05:29 pm »
Quote
1. The missile AIM-54 Phoenix (for the F14 Tomcat) got in service in 1974. This missile can fly 16 g at a top speed of more than 4,800 kph. G-forces are no problems for AI aircrafts.

The only time the missile flies at 16g is when it is fired - and in that case it will be destroyed in minutes anyway... so I don't see how that helps the point. ;)
Incidentally, that 16g is acceleration in the direction of flight. A better argument would have been the 50g acceleration missiles can undergo in the terminal phase of their interception. But again, that lasts for only seconds. The way to evade a missile is not only to try to lose lock, but to try to make it run out of speed before it hits you. If that missile keeps turning at that 50gs, it will run out of speed in a matter of seconds. (Also note how small a missile is compared to the fighter that launches it.)

2. WW2 fighters could also pull 9g turns. The difference between that and modern fighters is that now we have G-suits to help the pilot keep consciousness, and the better engine lets it retain more speed longer. Incidentally, the Stiletto was/is designed only 20 years in the future, and likely the Saracen will be older than 10 years (possibly even 30-40 years, much like F-15s/F-16s today) at the time of the game.

3. An AI-plane wouldn't be all that much smaller. Look at some modern UAVs, like the Globalhawk. What takes up the most space in an aircraft today are fuel tanks, engines, and other systems. In the Globalhawk, the space saved by removing the cockpit is actually used again in the satellite dish: http://www.strategie.com.pl/teksty/technika/bezpilotowe2/Global_Hawk-1.jpg. That space could be reclaimed by using a solid-state antenna the entire length of the airframe, but that cross-section shows just how much space is saved.

4. That is the best argument against needing airframes that last a long time. You're absolutely right that the life expectancy of interceptors against UFOs is probably in the single-digits, maybe the double digits with improved avionics. The only argument against that is that only the Stiletto is designed to go up against alien craft. The Saracen is a pure terran design for terran needs. (Also, the Stiletto was first flown in 2026. With a modern development cycle, it would have to be in the early concept stages within the next decade to meet that schedule.)


5. By performance, I meant aeronautic performance. Even if the airplane could pull and survive over 9 gs, it could be tactically unsound to do so. (ie: You'll lose a lot of altitude and airspeed) Also, especially in the case of two hypersonic vehicles approaching head-on, both sides would need sensors and computers to process that data anyway, plus they will initially start at over hundreds of miles apart, which leaves plenty of time to launch missiles. (And dropping bombs at mach 4: A human will likely designate the target ahead of time, fly over the target, and the computer drops the bombs at the right time. That's already how it's done today. Reaction time will have no part to play in that.) The only time you need instant reactions in this case is if you want a head-on guns kill - and that's probably a 10 second opportunity in a 10-minute fight.

Alien materials will be enough to protect a missile from hypersonic speeds, so there's no need of worrying about it burning up. (The Galilleo probe was also entering at interplanetary speeds, much higher than the AM missiles will get to unless launched from orbit)

Again, you're right that the question becomes "why risk a human pilot at all?" I think the answer is that alien ECM and jamming will hamper the effectiveness of a remote ground operator and the cost and performance of a purely AI-controlled aircraft will not differ significantly from a sensor-fusion design with a human pilot - so in the end the flexibility of having a human tactician onboard outweighs the combat and moral/political advantages of a purely AI-controlled pilot.

In addition, the pilot will likely survive being shot down. The particle beams and AM missile kill only by kinetic impact, so unless the cockpit is hit the pilot can eject and survive to give a debreifing.

In retrospect, perhaps the best method is a combination. A human pilot controls a flight of AI 'wingmen,' which take the risks and get shot at. The closer range limits the effects of jamming on the UCAVs, and the human is present to examine the situation and think tactically.

And, at the end, I could probably evoke Ken Burnside's Zeroth Law of Space Combat: People react better to human beings than silicon chips. :)


Doctor J:

The 2-mission life expectancy you give is only based on current game mechanics, which is simplified and buggy (1hp ships). The final game will probably be different. In comparison, Interceptors in the first X-COM would always survive unless you put them in range of Battleships or TerrorShips. It's up to the developers how far along this continuum they want to place things.

Plus, there are already plans for SAM sites, if they're not implemented already.

Offline Doctor J

  • Squad Leader
  • ****
  • Posts: 265
    • View Profile
Re: 2 questions on human aircraft designs
« Reply #22 on: April 23, 2008, 07:17:23 am »
@Psawhn: You bring up several well-considered points, and i will take my time to mull them over.  Right now i wanted to mention that i wasn't even considering the possibility of operating these things by remote control, a la Predator or Global Hawk.  In addition to questions of jamming, you'd have to consider the latency of the connection between the pilot and the vehicle.  A half second delay is not significant for reconnaissance, but would be a killer in a dogfight.  That's why i'm pointing toward having a self-sufficient AI onboard.  Thus, you wouldn't need to include room for the dish.  In any case, the Predator with a dish is already significantly smaller than comparable manned aircraft [probably the A-10 is the closest analog].

Your idea of a manned craft operating these things over short distances is worthy of further exploration, though.  How many would he be able to control at a time?  Also, would they all have to be launched from the same base, or would the Air Controller be able to launch new drones as needed [ideally only after having the target in sight, to prevent needing large fuel tanks in the drones]?

P.S. The anti-matter missile is kinetic energy only?  I had assumed that when it neutralizes normal matter there would be a burst of radiation bigger than a comparable H-bomb.

Offline Psawhn

  • Squad Leader
  • ****
  • Posts: 210
    • View Profile
Re: 2 questions on human aircraft designs
« Reply #23 on: April 23, 2008, 06:46:37 pm »
I'd consider the U2 to be a closer analogue to the Globalhawk, because they're both recon craft. Interestingly, the UAV is shorter, but has a wider wingspan than the U2-R. The RQ-4 is also longer than the SU-25 (but shorter than the A-10), but has half the wingspan of both.
Looking at that cross-section I posted, the elimination of the satellite antenna won't actually decrease the craft's length all that much. There's only so much room on the bottom to put sensor gear, and reducing the length might make it too cramped.


Maybe you and I have different definitions of self-sufficient AI. I treat that as not needing a human in the loop at all, and making tactical desisions (which enemies to engage, etc) on its own. The AI used in either a forward controller mode, or from ground-based installations, would be mostly self-sufficient - enough to engage in combat maneuvers on its own. The human is there so they don't accidentally shoot down an airliner or bomb friendly troops on the ground, in addition to being able to use better strategies and tactics. (It's more like an RTS than a flight sim for the human operators)

The role of a Forward UAV Operator would likely be a cross between flight lead of human wingman, and a Forward Air Controller for close air support. The unmanned vehicles will be the same size as any other modern fighter, possibly even just a regular fighter with no one in the cockpit to save cost. If the FUO needs more fighters, he'd have to request a flight be launched from the nearest airbase, and those aircraft would check in once within range. He'd give generic orders to fighters he controls, much like in an RTS. He'd have the options, though, to directly see the data from any of its sensors, and possibly take direct control if needed.

The arguments against short range UCAVs are the same as any short range fighters. Plus, the smaller a UAV, the better it would be just to send a SAM up there instead. I'm expecting these UCAVs to have similar survivability to any human-piloted craft in the same situation.


Also, you're right in that the detonation of an AM missile likely gives a burst of radiation, but there's barely enough fuel in the thing to keep it going at hypersonic speeds. Modern missiles actually use the shrapnel from its explosion to kill the jet, (and the jet rarely explodes in the air - it more falls out of the sky). The AM missile will be the same effect, except the shrapnel is going much faster.

 

Serrax

  • Guest
Re: 2 questions on human aircraft designs
« Reply #24 on: April 23, 2008, 10:29:22 pm »
Quote from: Doctor J
@Psawhn: You bring up several well-considered points, and i will take my time to mull them over.
Arguments are always "well-considered" if they support one's point of view.  ;D

Let's have a look, which agrument survives...

@Psawhn:

Quote from: Psawhn
  The only time the missile flies at 16g is when it is fired - and in that case it will be destroyed in minutes anyway... so I don't see how that helps the point. Wink
Incidentally, that 16g is acceleration in the direction of flight. A better argument would have been the 50g acceleration missiles can undergo in the terminal phase of their interception. But again, that lasts for only seconds. The way to evade a missile is not only to try to lose lock, but to try to make it run out of speed before it hits you. If that missile keeps turning at that 50gs, it will run out of speed in a matter of seconds. (Also note how small a missile is compared to the fighter that launches it.)       
Of course - and as state-of-the-art interceptors reach 9g, no missile can hurt them - as they reach 16 just at ignition...  ::)

Of course, the Phoenix can turn around at 16g.

Quote from: Psawhn
2. WW2 fighters could also pull 9g turns. The difference between that and modern fighters is that now we have G-suits to help the pilot keep consciousness, and the better engine lets it retain more speed longer. Incidentally, the Stiletto was/is designed only 20 years in the future, and likely the Saracen will be older than 10 years (possibly even 30-40 years, much like F-15s/F-16s today) at the time of the game.         
Do you really believe that?

G-suits are no modern invention - even the pilots of the F100 Super Sabre had them - 1954 (in contrast to the MIG-pilots). Also the F4 Phantom hat G-Suits, but the plane could only stand 6g.

No plane of WW2 could stand 9g.

Quote from: Psawhn
3. An AI-plane wouldn't be all that much smaller. Look at some modern UAVs, like the Globalhawk. What takes up the most space in an aircraft today are fuel tanks, engines, and other systems. In the Globalhawk, the space saved by removing the cockpit is actually used again in the satellite dish: http://www.strategie.com.pl/teksty/technika/bezpilotowe2/Global_Hawk-1.jpg. That space could be reclaimed by using a solid-state antenna the entire length of the airframe, but that cross-section shows just how much space is saved.
The Global Hawk is an aircraft for long-term suveillance - and not designt for high velocities. And for this mission, this shape and dimensions of the wings are optimal.

Further: The size has no meaning and AI pilots save a lot of stuff inside the aircraft (pressurized cabin, live support system).

Quote from: Psawhn
     The only argument against that is that only the Stiletto is designed to go up against alien craft. The Saracen is a pure terran design for terran needs. (Also, the Stiletto was first flown in 2026. With a modern development cycle, it would have to be in the early concept stages within the next decade to meet that schedule.)   
Absurd. You cannot 'wish' the stiletto to be the super-interceptor. It is the oldest interceptor from human's arsenal - and no use against bigger and faster UFOs. There's no way to upgrade the stiletto to the level of the Dragon interceptor - which will replace it.

Quote from: Psawhn
5. By performance, I meant aeronautic performance. Even if the airplane could pull and survive over 9 gs, it could be tactically unsound to do so. (ie: You'll lose a lot of altitude and airspeed) Also, especially in the case of two hypersonic vehicles approaching head-on, both sides would need sensors and computers to process that data anyway, plus they will initially start at over hundreds of miles apart, which leaves plenty of time to launch missiles. (And dropping bombs at mach 4: A human will likely designate the target ahead of time, fly over the target, and the computer drops the bombs at the right time. That's already how it's done today. Reaction time will have no part to play in that.) The only time you need instant reactions in this case is if you want a head-on guns kill - and that's probably a 10 second opportunity in a 10-minute fight.
I can hardly believe the you know what you're talking about...

Today, at a speed of mach 2 you cannot simply alter your course - as even slight turns cause high g-forces. The production of g-forces is always the result of speed and turnaround. And at mach 4, it is much worse. There's nearly no chance to avoid missiles.

And your bombing run at mach 4 works - as the target does'nt move at the same speed. It doesn't move at all.

And BTW: If you need a computer for combat - an AI pilot - why use a human pilot at all?

Quote from: Psawhn
   Alien materials will be enough to protect a missile from hypersonic speeds, so there's no need of worrying about it burning up. (The Galilleo probe was also entering at interplanetary speeds, much higher than the AM missiles will get to unless launched from orbit)     
The alien materials are not that advanced in UFO:AI. The Gallileo probe entered the atmosphere at an altitude where the atmosphere is much less dense than on earth (at an altitude of 10-20 km). Further: The probe was made to 2/3 of heat shield and one millimeter away from its course and the probe gets destroyed.

Quote from: Psawhn
Again, you're right that the question becomes "why risk a human pilot at all?" I think the answer is that alien ECM and jamming will hamper the effectiveness of a remote ground operator and the cost and performance of a purely AI-controlled aircraft will not differ significantly from a sensor-fusion design with a human pilot - so in the end the flexibility of having a human tactician onboard outweighs the combat and moral/political advantages of a purely AI-controlled pilot.
Pure speculation. There's nearly no use for your flexibility. It's simply that way: 'Go to these coordinates and intercept the enemy'.

Quote from: Psawhn
  In addition, the pilot will likely survive being shot down. The particle beams and AM missile kill only by kinetic impact, so unless the cockpit is hit the pilot can eject and survive to give a debreifing.
Absurd.

Any cinetic impact would comletely detroy any human aircraft. Plus, the rest of the antimatter will react with normal material and detonate - with several kilotonnes TNT. This additional effekt of the alien antimatter rocket-launcher is described in the UFO-wiki.

Furthermore - no human will survive a dropout at mach 4 at an altitude of 10,000 meters. Even today no one survies a dropout at mach 2.

Quote from: Psawhn
  And, at the end, I could probably evoke Ken Burnside's Zeroth Law of Space Combat: People react better to human beings than silicon chips.
Yeah, that's the reason for all the driver assistance technologies in the car nowadays.

Offline Psawhn

  • Squad Leader
  • ****
  • Posts: 210
    • View Profile
Re: 2 questions on human aircraft designs
« Reply #25 on: April 24, 2008, 02:29:51 am »
I don't think you're getting my argument that the simple act of any airplane or missile turning will cause that object to lose speed. The harder you turn, the more speed you lose. The faster you go, the more speed you lose while turning.

Quote
Of course - and as state-of-the-art interceptors reach 9g, no missile can hurt them - as they reach 16 just at ignition...  Roll Eyes
Of course, the Phoenix can turn around at 16g.
I did point out that in the final stage of a missile's flight, it will probably pull over 50g to try to hit its target. (I'm not so sure about the Phoenix - it's a big, heavy, missile designed to hit cruise missiles and bombers. Smaller missiles like the Sidewinder definitely pull more G's.)
Also, longer range missiles like the Phoenix and AMRAAM, unless fired from closer range, run out of fuel long before they reach their targets. That 16g acceleration, which increases as it runs out of fuel, is used to get the missile to a high altitude at high speed. They have to coast to the target after that. For quite a bit of their range, if your target simply makes a 1.5g bank and turns the other way, they'll outrun your missile.

Quote
Do you really believe that?

G-suits are no modern invention - even the pilots of the F100 Super Sabre had them - 1954 (in contrast to the MIG-pilots). Also the F4 Phantom hat G-Suits, but the plane could only stand 6g.

No plane of WW2 could stand 9g.
I'm fairly certain I remember watching a Dogfights! episode about a Divebomber in the Pacific facing up to a few Japanese Zeros, and surviving because he repeatedly pulled high G turns in order to meet each one head-on. You're right it might not have been 9 g, but I'm very sure it was 6g or more, and his rear gunner kept passing out from the turns.
I'm also sure the F-4 could survive more than a 6g turn, but I can't find anything except a snippet claiming a very brief 11g jink to evade a SAM.

Quote
The Global Hawk is an aircraft for long-term surveillance - and not designed for high velocities. And for this mission, this shape and dimensions of the wings are optimal.
Yes, the shape is that of a high-altitude glider (very long, thin wings), and isn't all that much smaller than another high-altitude, long range reconnaissance aircraft, the U-2. Its wingspan is actually longer than the U-2.

Quote
Further: The size has no meaning and AI pilots save a lot of stuff inside the aircraft (pressurized cabin, live support system).
Actually, that's just about all you'll save by removing the pilot. You still need the engines, control surfaces, landing gear, internal gun magazine, hydraulics, computers, radar, fuel tanks, backup generator, and probably more. If you want the airplane to carry missiles, it needs a powerful enough engine in order to actually carry the weight. If you want to download live TV feed from the sensors, you need an antenna of a certain size and power. The longer you want to be able to fly it, the more fuel you need.

Quote
Absurd. You cannot 'wish' the stiletto to be the super-interceptor. It is the oldest interceptor from human's arsenal - and no use against bigger and faster UFOs. There's no way to upgrade the stiletto to the level of the Dragon interceptor - which will replace it.
Where did this come from? I never said anything about the Stiletto being a superior design. My point was that the Saracen is a human design for human needs - so it is not a throw-away fighter by any means. The Stiletto is designed in the 2020's as a very maneuverable fighter to combat a completely unknown alien force. Neither were expected to have a mission life of 5 missions. Personally, if I were looking at lifetimes like that, I'd just use SAM batteries.

Quote
Today, at a speed of mach 2 you cannot simply alter your course - as even slight turns cause high g-forces. The production of g-forces is always the result of speed and turnaround. And at mach 4, it is much worse. There's nearly no chance to avoid missiles.
Yes, at higher speeds you get more acceleration at lower degrees-per-second turns. This is one reason turns at high speeds are wider and take longer to complete. However, you also get a lot more drag at high speed. That's another reason turning at high speed is tricky - if you turn too hard, you'd point the other way very quickly, but now you're travelling very slowly.

And what do you mean by no chance to avoid missiles? If I'm going mach 4, and you're going mach 4, and we both have a similar compliment of long range mach 6 missiles, then I'll simply launch my missile before you do and turn the other way. Now I'm heading away, probably at mach 3 because I lost a little speed in the turn. If I shot my missile and turned away from a far enough distance, any missile you launch will run out of fuel and crash before it reaches me. If you chase me to get in range of your own missiles, my missile will kill you first. Of course, if you simply turn away, then my own missile will run out of fuel before it hits you. In that case, we start all over again.

Of course, that's just one scenario. Maybe you have a wingman and I don't, in which case I'd probably just run away because no amount of agility will help me survive if you're playing smart. An AI-controlled plane pulling 12g's might survive one missile, but definitely not a second missile. Maybe I have a wingman, in which case I can try to lead you into a situation where he can shoot you with a missile, but you can't shoot either of us. Maybe I'd try to play chicken, getting into the range where I'm guaranteed a missile kill (but conversely, any missile you launch also kills me). Maybe I'd try to lead you into a friendly SAM battery. There are plenty of tactics I can use that give me an advantage without needing the extreme endurance a human pilot can't cope with.

Of course, as soon as you're controlling an antimatter-propelled UFO with advanced ECM and ECCM, firing hypersonic antimatter missiles at my little terran fighter with short-range TV-imaging missiles, then the game changes. In which case, if I were the commander, I should be shot if I keep trying to face your UFOs head-on with my little fighters. I need to use better strategies and tactics than you to get the upper hand.

Quote
And BTW: If you need a computer for combat - an AI pilot - why use a human pilot at all?
I'd use the computer for the things it's best at - calculating bomb release times, computing gun sight vectors, and missile hit probabilities. It's not so good for luring opponents into traps, reacting to unusual situations, and making tactical decisions.

Quote
The alien materials are not that advanced in UFO:AI. The Gallileo probe entered the atmosphere at an altitude where the atmosphere is much less dense than on earth (at an altitude of 10-20 km). Further: The probe was made to 2/3 of heat shield and one millimeter away from its course and the probe gets destroyed.
The Galileo probe entered the atmosphere at interplanetary speed - 47.4km/s. On Earth, the speed of sound at sea level is 0.34029 km/s, so that makes the probe travelling around Mach 140. The Jovian atmosphere is mostly hydrogen, though, so it'd be travelling at a lower Mach number than that. The fastest atmospheric speed alien materials can expect are reentry speeds - about 7.7km/s if entering from LEO, or about 11km/s if entering directly from Lunar orbit. That's Mach 23 and Mach 32, respectively. Well, actually the alien's engines let them slow down more before entering the atmosphere, so their limit could very well be lower than that.

Quote
Pure speculation. There's nearly no use for your flexibility. It's simply that way: 'Go to these coordinates and intercept the enemy'.
What if the enemy isn't exactly where those coordinates say it is? How does it determine which of the radar contacts it has actually is the enemy? Which strategy does it use to engage the enemy? What if the enemy behaves differently from what the AI and its programmers expected? There's a lot more to fighter combat than simply trucking missiles out to a point and launching them at any radar contact that comes near.

Quote
Any kinetic impact would comletely detroy any human aircraft. Plus, the rest of the antimatter will react with normal material and detonate - with several kilotonnes TNT. This additional effekt of the alien antimatter rocket-launcher is described in the UFO-wiki.
The missile simply does not contain enough antimatter to make that large an explosion. The wiki says nothing about that - the closest it gets to is saying "even a proximity detonation of the antimatter fuel is enough to take out a fighter jet," which leaves wide interpretations on how close this proximity detonation is. What's likely is that most of the fuel has been expended by the time the missile reaches its target, leaving just enough to turn the casing into hot shrapnel.
There's very little difference between this hot shrapnel and modern missile shrapnel, except that modern is probably Mach 4 and alien is twice that. That's only four times the kinetic energy, assuming the same mass of shrapnel.

Quote
Furthermore - no human will survive a dropout at mach 4 at an altitude of 10,000 meters. Even today no one survies a dropout at mach 2.
Then jettison the entire cockpit. The B-1, a supersonic bomber, already does that.

Serrax

  • Guest
Re: 2 questions on human aircraft designs
« Reply #26 on: April 24, 2008, 10:46:51 am »
Well...

Quote from: Psawhn
I don't think you're getting my argument that the simple act of any airplane or missile turning will cause that object to lose speed. The harder you turn, the more speed you lose. The faster you go, the more speed you lose while turning.
I get your point - but this counts just for today's maneuvers. More to that under the point of air tactics.


Quote from: Psawhn
I'm fairly certain I remember watching a Dogfights! episode about a Divebomber in the Pacific facing up to a few Japanese Zeros, and surviving because he repeatedly pulled high G turns in order to meet each one head-on. You're right it might not have been 9 g, but I'm very sure it was 6g or more, and his rear gunner kept passing out from the turns.
Sorry, but this is no useful information. Every divebomber can outdive a Zero.

And nearly every allied fighter/fighter-bomber can outdive a Zero. The Zero is an extremely light and agile construction without plating. In contrast to that, all allied aircrafts where pretty heavy and with stronger structure.

Quote from: Psawhn
[...] I'm also sure the F-4 could survive more than a 6g turn, but I can't find anything except a snippet claiming a very brief 11g jink to evade a SAM.
In fact, my information about g-forces in regard of the Phoenix and the F4 are from a little video clip, commented by an 'expert'. The F4 was a UAV (you know these orange-red colour), a target for a Phoenix. And thereby this expert explained, that the F4 turns with 6g, but the Phoenix hit it with a 16g turn.

Furthermore, a couple of texts talk about that issue. They point out, that the F-16 was the first plane which can stand 9g and all others can stand maximal 6g or 7g.

Quote from: Psawhn
Yes, the shape is that of a high-altitude glider (very long, thin wings), and isn't all that much smaller than another high-altitude, long range reconnaissance aircraft, the U-2. Its wingspan is actually longer than the U-2.
The range of the Global Hawk is TWICE the range of an U2!

Quote from: Psawhn
Actually, that's just about all you'll save by removing the pilot. You still need the engines [...]
I assume, you need perhaps 3 cubic meters for a human pilot in the best place of the plane (in the front, central).

As all modern fighters use fly-by-wire and autopilots, there's nearly no additional tech to install for an AI pilot.

Quote from: Psawhn
The Stiletto is designed in the 2020's as a very maneuverable fighter to combat a completely unknown alien force.
My you please quote the text, as I cannot find that. It seems to me, the only arguments for the Stiletto are - it is cheap and 'available'.
 
Quote from: Psawhn
And what do you mean by no chance to avoid missiles? [...]

Of course, as soon as you're controlling an antimatter-propelled UFO with advanced ECM and ECCM, firing hypersonic antimatter missiles at my little terran fighter with short-range TV-imaging missiles, then the game changes. In which case, if I were the commander, I should be shot if I keep trying to face your UFOs head-on with my little fighters. I need to use better strategies and tactics than you to get the upper hand.
That's exactly the point. Standard fighter tactics from nowadays are almost useless against UFOs - as no long-range missiles work.

The tactic is quite simple:

- find the UFO by guidance from the base
- approach to the enemy
- fire your weapons until you hit the target, the target hits you, or you run out of ammo
- if you're lucky, you survive these 10 seconds - return to base

Due to the extreme high velocities, there are hardly any other useful tactics. Especially not for a single interceptor. For more interceptors, maybe some kind of the "Rudeltaktik" will do - like in WW2 the german submarines used against convoys, to attack simultaneously from different directions. But the options are strictly limited - as you have to attack head-to-head, because neither the interceptor nor your missiles are cabale to hit the UFO from behind and probably not from the side.

Quote from: Psawhn
I'd use the computer for the things it's best at - calculating bomb release times, computing gun sight vectors, and missile hit probabilities. It's not so good for luring opponents into traps, reacting to unusual situations, and making tactical decisions.
Imho is your tactic with an foreward human 'UAV observer' not better, than the use of complete AI pilots.

Quote from: Psawhn
That's Mach 23 and Mach 32, respectively. Well, actually the alien's engines let them slow down more before entering the atmosphere, so their limit could very well be lower than that.
Yes, the UFOs behave in the atmosphere in dimensions of human technology. There's no information about g-compensation for UFOs - but it's certain, that they use some kind of gravity technology. This technology could lead to g-compensation which would the UFOs allow much more maneuvers (plus: aliens could stand more g-forces than humans).

Quote from: Psawhn
What if the enemy isn't exactly where those coordinates say it is? How does it determine which of the radar contacts it has actually is the enemy? Which strategy does it use to engage the enemy? What if the enemy behaves differently from what the AI and its programmers expected? There's a lot more to fighter combat than simply trucking missiles out to a point and launching them at any radar contact that comes near.
Well, there's a little bug in UFO:AI. Your base radar works 100% correct. The UFO is despite all ECM exactly on the position where we expect it thanks to our radar.

The result is, we're back to the 70s - a time in which the interceptors had to be guided by the base to their targets.

Quote from: Psawhn
The missile simply does not contain enough antimatter to make that large an explosion.
Ok, you're right.

Due to the wiki, the don't need it - as they have an excellent guidance system.

Quote from: Psawhn
Then jettison the entire cockpit. The B-1, a supersonic bomber, already does that.
Well, this system was installed in the B1A. They removed it by the upgrade to B1B - as this system is heavy and not so reliable compared to ejection seats. The F-111 still has such a system, but I don't know any modern aircraft with these systems.

rimis

  • Guest
Re: 2 questions on human aircraft designs
« Reply #27 on: April 24, 2008, 03:20:05 pm »

Furthermore - no human will survive a dropout at mach 4 at an altitude of 10,000 meters. Even today no one survies a dropout at mach 2.


One pilot successfully ejected at mach 3.25 and at altitude of 25,000 meters from sr-71.

Offline Psawhn

  • Squad Leader
  • ****
  • Posts: 210
    • View Profile
Re: 2 questions on human aircraft designs
« Reply #28 on: April 24, 2008, 08:48:57 pm »
Quote
Sorry, but this is no useful information. Every divebomber can outdive a Zero.

And nearly every allied fighter/fighter-bomber can outdive a Zero. The Zero is an extremely light and agile construction without plating. In contrast to that, all allied aircrafts where pretty heavy and with stronger structure.
The pilot didn't survive by diving away, but by turning into each Zero as it made a run on him. I don't remember the exact reason he couldn't simply dive away, but I suspect that if he did, at least one of the Zeros could shoot him down before he would have been out of range.


Quote
In fact, my information about g-forces in regard of the Phoenix and the F4 are from a little video clip, commented by an 'expert'. The F4 was a UAV (you know these orange-red colour), a target for a Phoenix. And thereby this expert explained, that the F4 turns with 6g, but the Phoenix hit it with a 16g turn.

Furthermore, a couple of texts talk about that issue. They point out, that the F-16 was the first plane which can stand 9g and all others can stand maximal 6g or 7g.
I'm sure I've read many times that dogfighting missiles, like the Sidewinder, have to pull 40 to 50 g in order to hit a maneuvering target. And I did just read that the F-16 was the first US fighter to be designed to withstand 9g.

Quote
The range of the Global Hawk is TWICE the range of an U2!
I think that has a lot to do with its increased wing aspect ratio, a more efficient engine, and the ability to fly at a leisurely pace.

Quote
I assume, you need perhaps 3 cubic meters for a human pilot in the best place of the plane (in the front, central).

As all modern fighters use fly-by-wire and autopilots, there's nearly no additional tech to install for an AI pilot.
You're right that there'd be nothing additional to install for an AI pilot. I think 3 cubic metres is a bit much, though.
For a pilot, you'd need: a canopy, air conditioner, emergency oxygen tanks, and a pressurized cockpit with room for an ejection seat, avionic controls and displays, maps & other gear, and the pilot. All that probably fits in the volume directly below the canopy. I can't see anything to contradict that in this cutaway of an F-35B http://www.defenseindustrydaily.com/images/AIR_F-35B_Cutaway_lg.jpg.

Quote
My you please quote the text, as I cannot find that. It seems to me, the only arguments for the Stiletto are - it is cheap and 'available'.
From here: http://ufoai.ninex.info/wiki/index.php/Aircraft/Stiletto-class_Interceptor. The first brief is dated 2026, and later Navarre mentions in the Addendum that "It's hard to believe we built these little things in 2026." Navarre confirms its agility: "What we have here is probably the most manoeuvrable aircraft ever built..." We also know only PHALANX designed and built it, because the report is an internal report, plus Navarre wonders why no one ever knew what kind of gold they were sitting on.

Quote
That's exactly the point. Standard fighter tactics from nowadays are almost useless against UFOs - as no long-range missiles work...
My point is that the very first interceptor designed to go up against the known capabilities of UFOs is the Dragon, followed by the Stingray, which incorporate alien technologies. The Saracen was designed to go up against Terran fighters, and the Stiletto was designed to be the best it could be against anything.
Those tactics you give are also specific to the current gameplay mechanics, and they'll definitely change sooner or later.

Quote
Imho is your tactic with an foreward human 'UAV observer' not better, than the use of complete AI pilots.
I don't quite get what you're saying here, but I do think a forward UAV operator probably is the best compromise between the two worlds.

Quote
Yes, the UFOs behave in the atmosphere in dimensions of human technology. There's no information about g-compensation for UFOs - but it's certain, that they use some kind of gravity technology. This technology could lead to g-compensation which would the UFOs allow much more maneuvers (plus: aliens could stand more g-forces than humans).
I'm not so certain they have g-dampeners, at least not ones powerful enough to provide a force of more than two to three g. Such technology is also very applicable in creating a linear accelerator that can propel nonmagnetic uncharged objects, yet both the missile launcher and particle beams use electromagnetic acceleration. The only gravity technology that I know of that the aliens use are jump drives and sensors.

Yes, the aliens can survive higher forces than humans, but their UFOs are very inefficient aerodynamically, and do have to obey the same aerodynamic laws as our fighters. A high speed turn will still slow down their ships considerably, tempered by the fact that their engines have much more power. Our fighters turn hard at high speed because of the air, UFOs turn hard at high speed despite the air.

Quote
Well, there's a little bug in UFO:AI. Your base radar works 100% correct. The UFO is despite all ECM exactly on the position where we expect it thanks to our radar.

The result is, we're back to the 70s - a time in which the interceptors had to be guided by the base to their targets.
The scale of the geoscape easily allows 'exactly where we expect it to be' to encompass an area measuring at least tens of km on a side, possibly up to hundreds of km. Its location is probably a best guess by the radar operators, despite the fuzzy returns and ECM.

Quote
Well, this system was installed in the B1A. They removed it by the upgrade to B1B - as this system is heavy and not so reliable compared to ejection seats. The F-111 still has such a system, but I don't know any modern aircraft with these systems.
The B-1B has a slower top speed and different mission profile, too, making it less vital for an ejection pod. Few modern aircraft travel past mach 2, and so likely do not need the ejection seat. I expect in the future it would become more reliable and attractive for hypersonic craft.

Offline Doctor J

  • Squad Leader
  • ****
  • Posts: 265
    • View Profile
Re: 2 questions on human aircraft designs
« Reply #29 on: April 25, 2008, 08:51:09 am »
I still don't see the benefit of having a pilot. 

1) We've already agreed that these craft would be "making tactical decisions" on their own.  It turns out my estimate of lag time was a little high, it would actually be quarter second round trip between, let's say, Africa and North America.  Nonetheless, it's still too long to wait for fire approval.  By the time permission to engage has been given, the target is already out of reach - or your craft is already falling from the sky.  So ground based control is right out.  The forward controller would be close enough to eliminate the lag, but for it to have all the comm circuitry to control several fighters it would have to be much larger, like an AWACS.  As such, i don't see it traveling fast enough to keep up with the fighters.  Since the onboard AI is doing the fighting, the only thing the controller can do anyway is to give the fighter a different vector or withhold permission to engage.

2) Shooting airliners or bombing ground troops: these are non issues.  The Harvesters have effectively ended civil aviation.  Our craft are simply not equipped with air to ground ordnance, so hitting surface targets is another straw man.  I think we can assume that at the velocities and distances we're contemplating, there won't be any visual confirmation of the target.  Anything up there that doesn't respond to an IFF squawk gets light up, period.

3) "Use the computer for the things it's best at".  Modern Expert Systems computers are already better [quicker] at making timing critical decisions than people.  A live pilot would only slow things down.

4) Here's a quote: the computer is "not so good for luring opponents into traps, reacting to unusual situations, and making tactical decisions."  I don't think we're going to be luring Bug Eyed Monsters anywhere until we understand their psychology, so it won't be happening until late game.  At that point we're flying greatly improved craft, and no longer need these disposable craft we're considering.  Reacting to unusual situations: okeh, i'll hand you that.  But by definition, most flights don't have unusual situations.  How many pilots have to get killed before one gets an opportunity to exploit?  As to the last point, Psawhn already said that the robot craft would be making tactical decisions on its own.

5) Size of craft: engine, wings and flight control surfaces are all proportional to the payload and any other weight/volume that doesn't contribute to lift and control.  Eliminating the pilot allows you to get rid of the ejection seat, all [almost all] levers, buttons, gauges, etc., life support, pressurization, and all your backup systems.  Additionally, the requirement that the pilot be able see out [and have easy access in and out] leads to wasted or inefficiently utilized space.  If we decide to dump it all but keep the ammo and fuel storage the same, the engines, etc. can be shrunk accordingly.  OTOH, we can keep the frame the same size but use all that extra space for increased fuel and or weapons.