Miragedriver
Brigadier
Thank you. I was unaware of the AL-225 production had begun.
JF-17/FC-1 Fighter Aircraft thread
- Thread starter johnqh
- Start date
Thank you. I was unaware of the AL-225 production had begun.
Miragedriver
Brigadier
Well Friend here are some responces:
1. The Useful load figures for FC-1 / JF-17 seem to be wrong. It was 3600 KG, and then this figure was revised upwards close to 4000 KG. I do not think that your figures are quite correct.
Response to question 1: Data was taken from Pakistan Aeronautical Complex. I didn’t pull it out of thin air. I have not seen anything offical that states 4000kg
2. JF-17 is a true multi-role. With the just 550KM range L-15 can be nothing other than a point defence fighter in addition to being a trainer.
Response to question 2: Yes the combat radius of the L-15 is only 550km+ and that of the JF-17 is 1,352km (almost triple). The combat radius of the JAS 39 is 800 km. does that make the JAS-39 inferior to the JF-17? No. It’s just a handicap that the aircraft has. Additionally, the combat range can vary depending on the armaments carried. As I mention previously do you really what to hang everything on the aircraft or use it in a specific roll such as air defense with 4 or six missiles, or a precision strike?
Additionally once the second seat is removed there will be additional space for fuel and other equipment.
3. While the TWR for L-15 is reportedly greater than 1, that is really because of the limited fuel capacity. At similar fuel capacity FC-1 / JF-17 could have a similar TWR as well.
Response to question 3: See response 8. Given the same fuel and AtoA armaments the L-15 will still have a high thrust to weight ratio. It’s simple mathematics.
4. It is important to note that FC-1 / JF-17 has probably the lowest operating cost of multi-role combat jets. That is because it is single engine, has easy access to parts and components that need to be serviced. Consequently it has a much shorter turn-around time. It also needs comparatively fewer support staff. In a war scenario these things count. I doubt that with two engines L-15 could match these advantages. Its two engines might be good for redundancy, and then the question arises if it can stay aloft with one engine. If it can not do that, then what real advantage could it have with its being twin-engined?
Response to question 4: Two engines require more maintenance than one just based on numbers. However, not all engines are the same. Would you prefer to do maintenance on one ATAR-9 engine or two M-88 engines? If you ask any French Air Force maintenance personnel they will say the M-88 is lower maintenance. However for the sake of a friendly discussion I will concede the maintenance issue based on two engines and not one. However the Chinese feel that the L-15 is an extremely low maintenance aircraft with well throughout access panels and easily removable engines. So your argument that the JF-17 is less maintenance than the L-15 is unproven and only speculation.
Additionally the survivability of two engine aircraft is greater than that of one engine.
5. While PAF is considering installing a bigger and better AESA radar in Block III, I doubt one could do much within the limitations of L-15. Just look at the nose to see the maximum size of radar it can carry. It is not merely a matter of spending money to get a better radar / avionics.
Response to question 5: A single seat version of the L-15 would have a larger radom than the trainer version. As an example see what the English did with the radom on the Hawk 200 vs. the Hawk trainer. Additionally the radom on the JAS-39 and the Tejas is smaller than that of the JF-17. It all comes done to the avionics used and if it is used in conjunction with AWAC aircraft, AWAC UAV. What if you are in a HIGH ECM environment? Your radar is useless. Again I will harp on the JAS-39 that can operate in a high ECM environment without its radar, but instead with a superb datelink system.
6. What types of weapons can L-15 carry? That is an important question. How many hard points does it have, what is the capacity of those hardpoints? Can it carry a potent BVR missile? Can it have a RADAR with greater range than a possible BVR missile?
Response to question 6: In a single seat version probable three under each wing and one on the wing tips, possibly one on the centerline. Combined probable not more than 3000kg (similar to the YAK-130). Again see the response to question 5. However if the Israelis could make the Mig-21-2000 operate with BVR missile system and well as help the Brazilians and Chileans operate BVR systems on the F-5Es (which by the way has a very small radom) there would not be a problem with the L-15. Granted all this makes the aircraft cost more probable another 1.5 to 2 million dollars US
7. The service life of an aircraft can not conclusively be determined in advance. A lot depend upon the use. A lot also depends upon the capacity and capability to upgrade the airframe and aircraft. PAF is still flying 45 years old Mirages. So the question of life of an aircraft is relative and depends upon design, usage, and overhaul. I do not know what usage do the jet trainers go through, but it can not be as gruelling as a hard hitting multi-role combat airplane.
Response to question 7: You could probable fly an aircraft 100-years if it was at a rate of 40 hours a year. That’s not the point. The JF-17 airframe is designed for a service life of 4,000 flight hours, or 25 years, the first overhaul being due at 1,200 flight hours. See article
The L-15 has an airframe design life of 10,000 flight hours. By having an aircraft that is less expensive that allows you to:
a) Purchase more
b) Train more
c) And by progression of logic a and b will help develop better tactics
8. You have mentioned that L-15 is more manueverable. I wonder how you arrived at that conclusion? It is certainly not as fast. Moreover, with future engine upgrade with RD-93MA or WS-13, JF-17's TWR is set to rise above 1. Once the plane gets full FBW as it should, it would go beyond that too with all the weight saving etc...
Response to question 8: The JF-17 is a heavier aircraft, at least by 2000 kg in the empty weight condition. Now add similar fuel and armaments the aircraft is heavier. Look at the thrust of the two Ivchenko Progress AI-222K-25F turbofans and that of the RD-93 ... don’t just accept what is being preached… take the time to look at the higher thrust-to-weight ratio, and lower wing loading and higher max-G. that will answer your question.
I am sure that L-15 is good for its own niche. But it can hardly be suitable for roles for which FC-1 / JF-17 has been designed. For all the hassle of converting a trainer into a true combat plane, it would be better to just go ahead and purchase a well-designed combat plane.
Once specifications for JF-17 Block III are released, we can truly appreciate its capabilities and potential.
For now JF-17 is a 3rd generation aircraft, not fourth. Here are my references to back it up:
[1] From The News, Pakistan: "The JF-17 Thunder is a light combat aircraft, a single-engine fighter with all-weather capability, which Pakistan has developed with the help of the Chinese. It is a Third Generation fighter that has been so designed that it can take on the fourth-generation fighter aircraft." [The News,Pakistan ^ | 2/8/2008 | Ali Abbas Rizvi ]
[2] From Global Security: “FC-1 airplane had achieved the Third Generation fighter aircraft synthesis"
[3] Here is an additional reference from the Chinese Embassy to confirm the JF-17 is 3rd generation, in addition to the previous two.
[4]From The Chinese Embassy ( Quote: "Pakistan Air Force officials told APP that the aircraft has comprehensive combat capability of a Third Generation fighter."
From GlobalSecurity ( Quote: "the FC-1 airplane had achieved the Third Generation fighter aircraft synthesis fighting efficiency"
The JF-17, while being a cost effective replacement for PAF's older fighters like the Q-5s and the Mirage-3s is not a 4th gen fighter by any stretch of imagination. Its upto date avionics while being capable can't plug one gap that differentiates a 3rd generation aircraft from a 4th generation one -- fly-by-wire controls. FBW is always the deciding factor in classifying an aircraft as a beyond 3rd generation. This is not to mean that the JF-17 will not be a capable aircraft. Oxymoronic as it may sound, frequently, older generation aircraft are more capable than newer generation aircraft. The "generation" classification is more a reflection of the technology than capability. Other factors include functions like serviceability and ease of use which, while being better in a newer gen aircraft does not increase "capability" per se. To give an example, the F-14 tomcat, which was replaced in United Sates Navy service by the F/A-18 Hornet is about half a generation behind the hornet but yet, it is capable of many functions the hornet is incapable of.
Anyway, PAF already has a 4th gen fighter in service, the F-16 which its pilots very well indeed.
Please do not take these responses as combative. We should never take what we are spoon feed or believe dogmatically to be the truth. That’s why we are all here is to have an open exchange of ideas and knowledge, backed up by facts.
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SteelBird
Colonel
JF-17 is third generation by what standard? Chinese or NATO? Don't forget that Chinese's 3rd gen means NATO's 4th gen. I don't think a multi-role aircraft fit with FBW, glass cockpit, BVR, 8+ G is classified as 3rd gen by NATO's standard.
Source:
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@ Miragedriver.
I see where you going this with L-15 vs JF-17 thread.
L-15 is only bit slower in top speed.
pulls about same Gs.
cheaper.
more airframe hours.
etc etc
while I see that L-15 seems to have the merits on paper, however I would caution this approach and here is why.
Advance trainers like L15s are designed to have longer life. they pay for it in having 1) heavier structures. 2) less useful envelope.
I am not talking with numbers and charts here so you just have to bear with me.
when I say less useful envelope here is what I mean. for example. On the aerodynamics side, an advance trainer may be able to reach 1.6M while a combat fighter may reach same or little bit more at 1.8 M at 36000 ft. but what about time to climb? under what pay load conditions. at 1.6M what Gs can a typical loaded fighter pull? or what about at 250-350 kts how many gs can each pull with a certain combat loading?
advance trainers almost always assume that most of time airplane would be may be half fuel and pilot only. and the higher Gs it pull would be at a lower speed (relatively speaking), as it is safer to do so. an advance trainer is always designed to give as good an handling quality as possible especially at lower left part of envelope, and since it is not going to war, everything else can be sacrificed.
So an advance trainer's wing almost always tend to cover the left part of envelope more. the low speed stall side. what it sacrifices are typically the g-capability on the right side, or buffet boundary, Simply put it, it may not be able to pull enough gs at higher speeds with a meaningful load, with out going to buffet.
a fighter on the other hand is designed to pull alot of Gs, with a war load, with out going buffet limiting at a higher mach number. Its wings are designed to do so. its number 1 goal for its wing design from conception is almost always try to cover the right side of envelope.
now straight and level and given enough time and fuel, both airplanes can reach that Maximum mach number on brochure. but Time to reach it, at what loading, and how many gs it can pull under what loads is what separates fighters from trainers.
Do you want to have an airframe that can not pull any meaningful Gs above 300 KTs at 30000 ft? and accelerates poorly to its top speed? for a country's top and only fast airdefence fighter? I don;t think so.
so the key numbers, may be misleading on the product labels!
Now if you want to redesign the wings...
Thats alot of $$$$$$$$$
I see where you going this with L-15 vs JF-17 thread.
L-15 is only bit slower in top speed.
pulls about same Gs.
cheaper.
more airframe hours.
etc etc
while I see that L-15 seems to have the merits on paper, however I would caution this approach and here is why.
Advance trainers like L15s are designed to have longer life. they pay for it in having 1) heavier structures. 2) less useful envelope.
I am not talking with numbers and charts here so you just have to bear with me.
when I say less useful envelope here is what I mean. for example. On the aerodynamics side, an advance trainer may be able to reach 1.6M while a combat fighter may reach same or little bit more at 1.8 M at 36000 ft. but what about time to climb? under what pay load conditions. at 1.6M what Gs can a typical loaded fighter pull? or what about at 250-350 kts how many gs can each pull with a certain combat loading?
advance trainers almost always assume that most of time airplane would be may be half fuel and pilot only. and the higher Gs it pull would be at a lower speed (relatively speaking), as it is safer to do so. an advance trainer is always designed to give as good an handling quality as possible especially at lower left part of envelope, and since it is not going to war, everything else can be sacrificed.
So an advance trainer's wing almost always tend to cover the left part of envelope more. the low speed stall side. what it sacrifices are typically the g-capability on the right side, or buffet boundary, Simply put it, it may not be able to pull enough gs at higher speeds with a meaningful load, with out going to buffet.
a fighter on the other hand is designed to pull alot of Gs, with a war load, with out going buffet limiting at a higher mach number. Its wings are designed to do so. its number 1 goal for its wing design from conception is almost always try to cover the right side of envelope.
now straight and level and given enough time and fuel, both airplanes can reach that Maximum mach number on brochure. but Time to reach it, at what loading, and how many gs it can pull under what loads is what separates fighters from trainers.
Do you want to have an airframe that can not pull any meaningful Gs above 300 KTs at 30000 ft? and accelerates poorly to its top speed? for a country's top and only fast airdefence fighter? I don;t think so.
so the key numbers, may be misleading on the product labels!
Now if you want to redesign the wings...
Thats alot of $$$$$$$$$
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Miragedriver
Brigadier
Thanks i.e. for getting my point and for the explaination. I was trying to draw similar line with the T-38 Talon and its evolution to the F-5E. If you see the Jf-17 and the L-15 in plan view they are almost the same size. Although I agree with most of what you said, you will have to admit that this smaller aircraft has the potential to become something more than what it currently is. I'll try to express myself better in the morning my English deteriorates when I'm tired. Thanks again for getting what I was driving at.
yes, T-38 to F-5 and now T-50 golden eagle to F/A-50
MAKO
Yak-130
Aermacchi M346
etc etc
on the fighter side F-CK-1. is also very similar.
L-15 does have potential. But the cost to bring it into the crowded light fighter market may be prohibitive. and once you do it commonality is not there to save the cost. it may be cheaper to have it separate.
If a smaller airforce wants a inteceptor it can buy FC-1, with couple of two seaters FC-1 as a conversion trainer.
If a larger airforce wants a fleet of dedicated advance trainer so it will save flight hours on its precious front line fighters airframes (typhoon/rafale/F-18/J-10 etc) it can choose to Equit itself with L-15/Yak-130/Aermacchi M346
How does it cheaper to have both? Precisely for Philippine air force to go for T/A-50 is to save cost as it combine the best of both world for a budget air force like them, rather than going for F-16.
As for L-15 not able to pull as hard as JF-17 is no proof. And JF-17 twin seat does not exist and its not even prototype stages. Small air force do not have the luxury like PAF to have F-16 trained pilot convert to single seat Jf-17. They need to immediately throw into the limited airframe they have to operate.
JL-15 IS unusual for trainer to have so much thrust for such a small weight and small airframes. None of the dedicated trainer on market is able to match JL-15 thrust and weight ratio. I believe hongdu when designing this plane is not just making a advance trainer but to give it a run for money of other 4th gen fighter.
1). read again what I said. for a larger airforce it is cheaper to have a Advance trainer to burn flight hours then a top of the line, full frontline capable, two seater version fighter. when all is said and done, the figure I have been seeing are about half, cost per flight hour.
for a smaller air force the savings accured by using trainer hours instead of the top jet's flight hours is not greater than the cost of another type. therefore an LIFT is not justified financially. got it?
2) as for "As for L-15 not able to pull as hard as JF-17 is no proof."
I am not talking about proof here. I made it abundantly clear in the last post. I am just telling you how an airplane designer would approach the problem of designing an advanced trainer vs. designing a fighter. the requirements are similar, yes, but there are cruicial differences that set them apart.
3) as for L-15's Thrust... its in line with yak-130's power plant. the distinguishing factor is the addition of a Afterburner.
probably this is what happened: PLAAF requirements is for it to have supersonic capability. so an after burner version of AI-222 was chosen to reliably put it into supersonic range.
actually if you want to compare power plant... L-15's cousin, the Aermacchi M346, actully has a more powerful power plant if compared at the non-after burning levels... which can get it into low supersonic mach number (at least what the advertising brochure say, probably in a shallow dive).
4) When people at Hondu (with Yakovlev's help) designed the L-15, it is probably doing exactly what everyone else do. strive to fulfill the requirements for its primary and probably the only customer for a long time... the requirements set down by The PLAAF. A Supersonic Lead-In-Fighter-Trainer. To save PLAAF valuable airframe hours on its J-10/J-11 fleet.
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Mirage, you know how the numbers struck me as soon as I looked at them? JF-17's combat radius of 1300km + and a ferry range of 3000 km+ vs L-15's 550 km combat radius and 3000 km + ferry range strongly suggest to me that the JF-17's range is measured using the same metric, probably with the same configuration of drop tanks and armaments; whereas the wildly differing combat radius and ferry range as given by L-15 suggest that they are using completely maximised configuration for both metrics; and that in turn suggests to me that you won't be getting the full payload for L-15 in practical missions.
At the end of the day, the JF-17 have done tonnes of full load and full weapon tests whereas L-15 loads are fairly speculative as of now and thus any figures given for its load and range should be taken with a grain of salt.
Dizasta1
Senior Member
I don't understand what the fuss is about!
Comparing JF-17 Thunders to JL-15 Falcons, are two different aircraft with completely different roles.
It all depends on what the customer wants and/or would prefer. And there is no evidence to suggest that the L-15 can perform as an Air-Defence fighter, with "large enough wings" (figuratively speaking) to conduct a full-spectrum Air-Defence/Air-Superiority role.
And I don't believe any Aircraft Manufacturer would shoot themselves in the foot by offering two different aircraft that can allegedly perform similar roles and one of'em is cheaper.
Puleeze ..... come up with a better argument next time!
Comparing JF-17 Thunders to JL-15 Falcons, are two different aircraft with completely different roles.
It all depends on what the customer wants and/or would prefer. And there is no evidence to suggest that the L-15 can perform as an Air-Defence fighter, with "large enough wings" (figuratively speaking) to conduct a full-spectrum Air-Defence/Air-Superiority role.
And I don't believe any Aircraft Manufacturer would shoot themselves in the foot by offering two different aircraft that can allegedly perform similar roles and one of'em is cheaper.
Puleeze ..... come up with a better argument next time!
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