986 replies to this topic

[milkyway]

EM shielding is not difficult to achieve and is provided on critical systems at the very least considering the war theatre possibilities in present day warfare. EM shielding is provided specially on aircraft designed to deliver nuclear weapons. Avionics and controls systems in particular are shielded from EMF however if the aircraft comes into contact with the shockwave of the blast, thats altogather a different issue.

However Fly by wire systems have multiple electronic redundancy systems, and if all fails the controls shift to direct mechanical/hydraulic actuation which is a standard contingency feature. However remember that relaxed static stability/ FBY aircraft are computer controlled and the controlled surfaces are constantly manipulated for controlled flight. If the system were to fail, even if hydraulic controls are available , controlling the aircraft would be very difficult to say the least. But stil, with regards to your question, all FBY aircraft have direct hydraulic/mechanical actuation systems in case of FCS failure.

this is the point. modern aircraft's maneuverability is primarily based on controlling a number of control surfaces, which are generally controlled by sophisticated algorithms (like gain scheduling, LQG, Kalman filters), which in turn are processed by flight control computers, which are at this point at best rad-hard microprocessors, which are no match to an EMP weapon which is specifically designed to produce very large power pulses (GW range), in this particular event you have at-best, a manually controlled (lot of reduced maneuverability) aircraft. Now either the flight control computers are EMP-hard, or you have a pilot manually flying an un-stable machine.

so it *might* make sense to review the whole design / specification process (not only of the electronics, but the control surfaces also) until or unless you have a proven EMP-hard FCS.

[Simpleton]

1. Are there any plans for a two seat version of Thunder?

2. When the Thunders begin to replace the Mirages, will the mirages be:

a. mothballed as reserve a/c
b. transferred over to the navy until the navy gets their own dedicated thunders
c. sold off

3. (Refer to q. 2 above)

a. if the mirages are mothballed what will happen to the personnel trained to overhaul them, as well as the mirage overhaul factory? If I remember correctly, the PAF likes to keep its support staff trained for one type of platform throughout their careers ( I think it was in one of the articles someone posted within the last two months in the air force forum), so will they be cross trained or let go?
b. If the mirages are to be transferred to the navy then will they go through another upgrade (like canards) at the rebuild factory to keep them competitive till the navy gets their own thunders (that is if that's in the works)?
c. isn't selling the mirages going to reduce the likelihood of selling the thunder to the same customer, (I gather the prices won't be too far off)?

4. Initially it was planned that some thunders would be equipped with Chinese avionics and weapons suites, and others with western (French) avionics and weapons suites and that the thunders with the Chinese electronics would be networked with the ZDK-03 AEW&C platforms, while the thunders with the French electronics would be networked with the Saab ERIEYE 2000 AEW&C platforms which would also control the F-16s. So as it stands now there will be no networking between any thunders and ERIEYES?

[safdar]

4. Initially it was planned that some thunders would be equipped with Chinese avionics and weapons suites, and others with western (French) avionics and weapons suites and that the thunders with the Chinese electronics would be networked with the ZDK-03 AEW&C platforms, while the thunders with the French electronics would be networked with the Saab ERIEYE 2000 AEW&C platforms which would also control the F-16s. So as it stands now there will be no networking between any thunders and ERIEYES?

Cant answer all youre questions, 

There are two things you are asking over here, LINK 16 for networking and MIL-STD-1553 bus protocol for weapons integration. 

I think both of these are available for JF-17 as it has been discussed way back. however linking with the AEWC (networking) is a secondary option anyway for fighter pilots as any system protocol used, there is a lag in data transmission hence pilot rely on the fighter jets own radars for interception and target acquisition. That brings us back to the question of what exactly is the JF-17 radar capable of.

[Munir]

1. yes
2. scrap/display/parked for spare parts till everything is no longer needed
3. engineers move pn to JF17/J10P/Block52 etc
4. that is untrue.

I think there is no need for more detailed reply.

[eterrestrial]

I have a question.

How good is L-159 ALCA. How good is it as a light weight fighter, how good is it as a multirole fighter? I have read that Bangladesh maybe interested in it, so is it what they really need, and is it a good alternative to a pure multirole fighter such as F-16 or JF-17?

[Simpleton]

I have a question.

How good is L-159 ALCA. How good is it as a light weight fighter, how good is it as a multirole fighter? I have read that Bangladesh maybe interested in it, so is it what they really need, and is it a good alternative to a pure multirole fighter such as F-16 or JF-17?

Let me get this straight, you're comparing an L-159 with an F-16 or JF-17?

A better comparison would be with something like the K-8, Alpha Jet, or BAE Hawk.

As to if Bangladesh really needing it, well if they're interested in it, then perhaps they need it. If they aren't interested in it, then I guess they don't need it.

[Skull-Buster]

Comparing L159 to an F-16 or JF-17 is like comparing a scooter with sports car.

[safdar]

I have a question.

How good is L-159 ALCA. How good is it as a light weight fighter, how good is it as a multirole fighter? I have read that Bangladesh maybe interested in it, so is it what they really need, and is it a good alternative to a pure multirole fighter such as F-16 or JF-17?

One thing to compare the Aero L-159 Alca is to the Lockheed F-104 Starfighter. Nuff said and don't take the pisss.

However to operate as a multimode fighter! Well I have reservations about that...HOWEVER! Comparing the L154 and F104 one only has to look at the wings and L-159 Alca is a dogfighting breed with very high wing loading (high wing loading due to small wings), which is a no no when it comes to low altitude low speed flights and SEAD roles. However a force to be reckoned with at high altitudes as a dogfighting aircraft as long as pilots are able to operate at high alpha are available.

Let me get this straight, you're comparing an L-159 with an F-16 or JF-17?

A better comparison would be with something like the K-8, Alpha Jet, or BAE Hawk.

As to if Bangladesh really needing it, well if they're interested in it, then perhaps they need it. If they aren't interested in it, then I guess they don't need it.

calm youre horses! he did not compare it with K-8 or a BAE hawk as such!

Comparing L159 to an F-16 or JF-17 is like comparing a scooter with sports car.

he did not compare it with a F-16 or a JF-17, now did he?

[Skull-Buster]

he did not compare it with a F-16 or a JF-17, now did he?

Well he did ask whether the L159 could be an alternative to the F-16/JF-17.

What is the range of the Grifo-L? A modern multirole fighter could detect and launch a BVR missile at the L159 before the L159 even sees it.

[safdar]

Well he did ask whether the L159 could be an alternative to the F-16/JF-17.

What is the range of the Grifo-L? A modern multirole fighter could detect and launch a BVR missile at the L159 before the L159 even sees it.

Brother skully. Im sorry. My apologies then. However the ALCA l-159 is a dogfighting breed in the sky but not compared to the F-16 or a JF-17 by a mile! As these fighters (F-16 or JF-17) have many roles other then just be a gangster in the sky.

[Simpleton]

One thing to compare the Aero L-159 Alca is to the Lockheed F-104 Starfighter. Nuff said and don't take the pisss.

However to operate as a multimode fighter! Well I have reservations about that...HOWEVER! Comparing the L154 and F104 one only has to look at the wings and L-159 Alca is a dogfighting breed with very high wing loading (high wing loading due to small wings), which is a no no when it comes to low altitude low speed flights and SEAD roles. However a force to be reckoned with at high altitudes as a dogfighting aircraft as long as pilots are able to operate at high alpha are available.




calm youre horses! he did not compare it with K-8 or a BAE hawk as such!



he did not compare it with a F-16 or a JF-17, now did he?

No, he didn't compare the L-159 with the K-8 or the Hawk or the Alpha Jet. He should have though, after all it makes more sense to do so. What he did say was:
1. How good is it as a light weight fighter?
You answered that quite well, dude. This a/c is a dogfighter. And Skull-buster pointed out the short-coming when comparing it with the F-16 or JF-17 in BVR combat.

2. How good is it as a multirole fighter?
Again the answer you provided was concise and to the point. And it's no different in its' gist from what I or Skull-buster stated.

3. Is it what they [Bangladesh] really need?
Only the Bangladeshi high command would be best suited to answer this.

4. Is it a good alternative to a pure multirole fighter such as F-16 or JF-17?
Again this was answered in the same vein as what all three of us think.

For one a/c to be considered as a potential alternative to another a/c, one must most logically compare the two. Hence it makes more sense to consider alternatives from within similar types of a/c. Of course I consider your opinions on the subjects of aircraft with due reverence considering your expertise and professional involvement in the field. Now aren't the Hawk, Alpha Jet and K-8 more suitable candidates when one speaks of L-159 being an alternative to--as opposed to a/c such as the multirole f-16 or the jf-17?

[safdar]

Now aren't the Hawk, Alpha Jet and K-8 more suitable candidates when one speaks of L-159 being an alternative to--as opposed to a/c such as the multirole f-16 or the jf-17?

Sorry I forgot I was engaged in this debate. You’re points are correct. I was just merely comparing the Aero Alca and starfighter on aerodynamics only, and there is a massive difference between the two on power plant and such.

Comparing it to the K-8 well, I think in some points the Aero Alca is better and in some points its not. For example the Alca would be efficient to intercept the K-8 (because Aero Alca has got a radar and K-8 does not!) however the K-8 is very effective in low altitude low speed flights that could devastate an airfield (even an armoured convoy) with K-8’s cluster bombs at low level flight dynamics and a navigator (twin seat), the Alca on the other hand requires guided air to surface missiles and no provision for any unguided anti-armour bombs because it would lack steady low altitude low speed flight and a navigator (single seat) as a K-8. The K-8 and Alca are not just nifty trainers for their respective countries Pakistan and Bangladesh, however the K-8 has a specific role to operate as a anti armour anti runway machine, the Aero Alca would end up competing against much heavier interceptor fighters as light weight fighter. Hence this Aero Alca does fall into a spot wholly reserved for Aero Alca alone, unless of course it was 1971! but even then the PAF starfighter would double over the Aero Alca before it bought it down.

[eterrestrial]

As for comparing L-159 with F-16, i never meant to compare it one on one or aircraft vs aircraft. I wanted to weigh the option of purchasing 100 L-159 against purchasing some 20 F-16 Block 52s. Because of the price difference.

Hence this Aero Alca does fall into a spot wholly reserved for Aero Alca alone

Isn't F-5 in the same category, or the cancelled F-20, or Hawk?

I got my answers for how good is it as a multirole fighter.

Only the Bangladeshi high command would be best suited to answer this.

I just wanted an opinion.

I want to add another question, i know it doesn't belong in this category but how good is wikipedia regarding information related to military?

[safdar]

As for comparing L-159 with F-16, i never meant to compare it one on one or aircraft vs aircraft. I wanted to weigh the option of purchasing 100 L-159 against purchasing some 20 F-16 Block 52s. Because of the price difference.

Well I understand you're logic behind such a question, however you are kind of missing the point why PAF wants those F-16s. They are our primary delivery system for nukes and the primary system for intercepting any hostile nuclear equipped fighter with BVRs, its the quality PAF is afternot the quantity.

Isn't F-5 in the same category, or the cancelled F-20, or Hawk?

you mean the USA F-20 Tigersharks? aerodynamically yes however Tigersharks were far more potent then the Aeroalca just not that versitile as the F-16s thou but were beautiful birds. I think only Malasia operates Hawks as CAS fighters becuase they have some twin engine air superiority fighters. India relies more on its scout helicpters not BAE Hawks.

I want to add another question, i know it doesn't belong in this category but how good is wikipedia regarding information related to military?

Its ok for quick referencing, just that historic and war events become biased! Its just a CNN sounding board.

[Simpleton]

What are the advantages of DSI over non-DSI inlets, besides the reduced complexity/weight? What are the disadvantages? How come the F-35 has them, but the F-22 doesn't (I mean the reasoning for including or excluding them)?

[safdar]

^^I think you’ve pretty much got the gist of the DSI theory the only disadvantage would be operating at different flight regimes because the inlets are fixed hence one only has a certain window to operate within unlike variable geometry inlets where one could actually fine tune the inlet gap. far too many benefits with DSI.

The interesting part about you’re question is why does the F-22 not have DSI and I came across a Chinese article written about this in which the writer mentioned a scientific paper published by NASA Langley research centre who carried out some tests of supersonic heat correlation on open and closed cavities, and this was carried out after the Columbia space shuttle disaster (2003) and only after this research did they realise that they could actually get away with DSI intakes even on a twin engine jet with out any excessive air friction heat degradation from the bottle neck created by the DSI bump and the air intake lips at supersonic speeds specially super sonic cruse. You see, only the F-22 was designed before this research was carried out, hence it was too late or too expensive to redesign the F-22 inlets, the F-35 JF-17 J-10B J-20 all followed the Langley research paper findings which was a thorough research conducted for the re-entry phase of the space shuttle. The Chinese follow American patents and scientific research papers diligently and learn from them. this is the only logical reason that makes sense that I have actually read but Im not 100% maybe 90%.

[safdar]

What are the advantages of DSI over non-DSI inlets, besides the reduced complexity/weight? What are the disadvantages? How come the F-35 has them, but the F-22 doesn't (I mean the reasoning for including or excluding them)?

Disregard my first post above (it could only be true if J-20 and F-22 could do near mach 3), I think this is more plausible, as I have found the real research paper that actually states that USA did conduct research on a new external compression caret type inlet on its twin engine F/A-18 HARV. F-18 has two inlets mounted on either side of the fuselage under the LEX, and for research they used fixed geometry (normally F-18 has variable geometry) and with a single 5 degree external compression ramp only on one right hand side inlet, this whole set-up would operate similar to a bump intake. There’s already plenty of evidence that external compression intakes are more efficient than internal compression intakes for M>1.5 to M=2 numbers ( doc, here ). Only that at subsonic mach numbers there is poor pressure recovery for external compression and that is the reason why they conducted this test.

Some excerpts from the paper are: www.nasa.gov/centers/dryden/pdf/88501main_H-2171.pdf

Inlet recovery levels are highest in the 4° to 20° AOA range.

Turbulence levels are lowest in the 4° to 20° AOA range.

Peak dynamic circumferential distortion levels are lowest in the 4° to 20° AOA range.

Basically that at low subsonic mach numbers (0.3~0.4) these were the best angle of attacks for optimum inlet operation. They obviously further researched on the F-16 which is already a fixed geometry inlet and we all know they went ahead with F-35 DSI and they swear by it to perform miracles.

Since USA did conduct fixed geometry external compression inlet research back in 1990~1993 why not use them in F-22?

One of the reasons could be that: (AOSS=angle of side slip, basically when turning)

At positive AOSS (nose-left aircraft position), the right-hand inlet was most efficient at all
AOA.

By rotating the aircraft nose-right (increasingly negative AOSS) while maintaining AOA, the inlet recovery, turbulence, and circumferential distortion descriptors were adversely affected.

The above would make sense to have two side by side inlets with just one engine, since one inlet would be effected due to fuselage interaction the other would be recovering (jf-17 F-35) or a single engine single DSI inlet (J-10 F-16). And this research also proves that it probably wasn’t the F-16 test-bed that allowed F-35s to have DSI inlets, it would be the F/A-18 HARV research.

But the Chinese have obviously proven that theory wrong that one inlet would be effected while the other recovering, because in a twin engine that scenario would of course be fatal because one engine would just flame-out if there is no inlet pressure while the aircraft banks. Beijing university also has a thesis on DSI intakes, only that Beijing university publicly declared the research paper only back in 2003 but not the research paper done on a twin engine fighter thou, and that would be of course the J-20 and that’s never going to get released anytime sooner. So the mystery will remain unsolved. But the indication is that someone in this field is ahead on research, unless the Americans come up with a negationist twist to some how discredit DSI inatkes contrary to their epistles already written about DSI inlets.

Beijing university also has a thesis on DSI intakes

[eterrestrial]

How does an Electrically scanned array radar perform better than a mechanically scanned array? In my opinion, in mechanically scanned array can physically move sideways, so it should provide better coverage and wider sweep, how does electrically scanned array match that without the radar dish moving?

Secondly, what is the coverage of radar around a fighter aircraft (width of the radar sweep)? Is it full 360 degrees around the aircraft or not?

And last, what is the function of the tail cone in Sukhoi aircrafts? Su-27, 30, 33,34,35,37?? (In Su su -30 Makhi it is used to pull the aircraft crashed due to 'state of the art' maintenance out of the ground).

[Chief of army staff]

Yaar! I don't like this new format. Older version was better.

[SUPARCO]

Salaam,



Please skip to 1:09.

Could someone please confirm whether this missile or it's equivalent is manufactured in Pakistan by any chance?

Salaam

[safdar]

Salaam,

Could someone please confirm whether this missile or it's equivalent is manufactured in Pakistan by any chance?

Salaam

All I can do is point in the right direction, maybe someone knows what it is exactly, french or Pakistani.

Looks like the SNEB rocket projectile with retarded tail definitely for target practice. If you know the calibre of the rocket, then check Pakistan ordnance factories website to see if its home made or not. Un-guided rocket projectiles are air force standard issue for close air support, they’re probably made in the thousands for air-to-ground and ground-to-ground roles.

A hint would be that the K-8 trainer also has a unguided rocket pod for similar roles.

[Jazba-e-Kashmir]

I found some old photos on my old mobile, and I remember i took some pictures of an afterburner-tube.
It was in a military aviation museum, here in denmark, which my class and i went for a visit.


But I never gained information about the afterburner tube,
.
So I have a technical question: Were the afterburner-tubes on the F-16s termed as "F-60s"?
As it says on the photos which i took it says, where the last servicing date was in the beginning of the 1980s.


Peace

[waqar0092]

first of all slam brothers on pdf,
i m glad that i could make finally a account on this site, i m been reading the pakistanidefence fourm since year 2000 or even before, this is my first post here,
brother i have noticed that Pakistan have some capable anti air craft missels , pleas look at video in you-tube, military exercises in Pakistan at 02:36 u wil find the 3rd vehicle from left side that military never reviled to have in inventory. my wilde guess , is it a hq-10 chineese sam ? or su-300,
i am sorry for my english skill , i did nt studied in english medium schools in Pakistan:).
Pakistan zondabad , salam

[Jazba-e-Kashmir]

wasalam
brother Waqar :-)

welcome to PDF, but please do introduce yourself in the introduction forum
i will welcome you there once again

Peace :-)

[Bilal]

first of all slam brothers on pdf,
i m glad that i could make finally a account on this site, i m been reading the pakistanidefence fourm since year 2000 or even before, this is my first post here,
brother i have noticed that Pakistan have some capable anti air craft missels , pleas look at video in you-tube, military exercises in Pakistan at 02:36 u wil find the 3rd vehicle from left side that military never reviled to have in inventory. my wilde guess , is it a hq-10 chineese sam ? or su-300,
i am sorry for my english skill , i did nt studied in english medium schools in Pakistan:).
Pakistan zondabad , salam

Can you post the link of the video, most probably it was am AR-2 mlrs, not a SAM.

[O J]

I had a quick query; was the 84th GDP; passing out in 1990 December given Omega watches by the PAF.
I would appreciate an informed response.
Also if anyone knows that if they are also given to current courses.

[Simpleton]

http://www.huffingto..._b_4117519.html