Flogger is always in some fantasy wawa land that’s for sure.

Never mind that restructuring a Lavi to fit a smaller engine also creates changes of CG that requires reprogramming of FBW code that is first of all, closed and proprietary intellectual property rights of a US firm. Then you have to reprogram the FBW back to fit a plane with the AL-31FN engine? Who would think of such absurdity but Mr. Flogger. He thinks designing planes are as easy as Lego blocks.

Look who is talking? 😀

As a matter of fact, the FBW of the Lavi was supplied by Lear Siegler, a US company. With the FBW outsourced, you can’t adapt the FBW from one plane to another just like that as FBW software has to be carefully tailored to each plane’s signature aerodynamics, flight characterstics, weight and center of gravity.

Crobato

you are forgetting Israel recieved Tech transfers with the Lavi. The US provided not only the technology but the know how, very similar to Japan, in fact Israel has been one of the nations that recieved more tech transfers from the US.

The US supplied only 40% of the IAI Lavi systems.

Flogger, using only the engine lengths is going to give you a very flawed answer. You also have to take their relative diameters into account, as well as the size and position of their accesory boxes.

I am not denying there are dificulties in re-engine any aircraft, however these difficulties can be overcome, not all re-engined aircraft meant changing the airframe however a re-engine is always possible

there are a few aircraft that remained the same after have been re-engined

F-15, F-14, MiG-23, F-16, MiG-21 etc etc…

These are some few aircraft that were modified and changed to some degree their airframe:

Tu-22M3/Tu-22M2: Tu-22M3 it has new inlets.
Kfir/Mirage V : the Kfir has a new rear end and fin.
MiG-27/MiG-23M: the MiG-27 has modified inlets.
MiG-25/MiG-31:The MiG-31 has new inlets and different rear nozzles
J-8II/J-8:The j-8II has new inlets
F-18E/F-18A/C:the F-18E has different inlets

basicly the IAI Lavi according to SIBNIA would be to the J-10, like the MiG-25 is to the MiG-31 in few words an ancestor

And where does this prove that the MiG-23 prototypes are powered by the much smaller R-11 or R-13 huh? The R-27 engine is already quite larger, the R-11 engine barely make 6000kg of thrust and the R-13 has yet to debut for MiG-21MF. You keep forgeting that later MiG-23s are much more extensively redesigned to fit R-29 and the R-35.

You seem to be running out of arguments, stupid.

are you talking to your self heheheheh

here is the data buddy

Length R-27:4.85 meters
Length R-29:4.96 meters
Length R-35:4.97 mters
Length R-13:4.60 meters

J-10 case
Length Al-31: 4.89 meters
length P&W 1120: 4.11 meters
Length WP-13:4.60 meters
WP-13 II:5.15 meters
F-100: 4.81 meters

Check the IAI Kfir case
Length SNECMA Atar 9:5.94 meters
Lenght J-79:5.30meters
See the difference in size betwen the J-79 and the Snecma Atar 9 and you can see re-engine any J-10 powered by a R-13/WP-13 with an Al-31 is possible

are modifications possible?
linkhttp://www.airwar.ru/enginer.html

Lol. The MiG-23PD is a fixed wing lift tailed delta jet and its really a very different aircraft from the variable wing MiG-23. It’s almost like a lift jet MiG-21. The swing wing plane aka MiG-23-11 prototype which is the basis for all MiG-23s to come already used the R-27.

So your example has no relevance.

did you read the links i gave? really specially this one
Первый полет опытного самолета “23-01” состоялся 3 апреля 1967г. (летчик-испытатель П.М. Остапенк&#1086. Истребитель, выполненный по нормальной схеме с треугольным среднерасположенным крылом и цельноповоротным дифференциально отклоняемым горизонтальным оперением, был оснащен маршевым двигателем Р-27-300 (1 * 51,0 кН/1 * 5 200 кгс, 1 * 76,5 кН / 1 * 7 800 кг&#1089 и подъемными двигателями с надфюзеляжными воздухозаборниками. Крыло имело мощную систему сдува пограничного слоя, что, в сочетании с подъемными ТРД, обеспечивало самолету длину разбега 180-200 м и пробег с тормозным парашютом 250 м (величина, рекордная для реактивного самолета такого класс&#1072. Самолет “23-01” успешно проходил летные испытания и был эффектно продемонстрирован на авиационном празднике в Домодедово 9 июля 1967г., однако 26 мая 1967г. А.В. Федотов поднял в воздух другой опытный МиГ – изделие “23-11/1” с крылом изменяемой геометрии, который и стал прототипом серийного истребителя. Самолет “23-11/1, как и “23-01”, был оснащен ТРДФ Р-27Ф-300 (5 200 / 7 800 кг&#1089, созданным под руководством Хачатурова и имеющим удельный расход топлива, на 25% меньший, чем ТРДФ Р-11Ф2-300, установленный на истребителе
http://topgun.rin.ru/cgi-bin/units.pl?unit=2040

In this article they claim the first MiG-23 prototypes were powered by R-27F-300 of 7800kg of thrust including the 23-11 with VG wing

Your problem is you can not see the R-27 had different variants and was developed in several versions some had much much higher yiends in the range of 10,000kg while others only of 7800kg of thrust or less

Lol. You have gone off the deep end. The so called prototype you mention is so different from the actual serial plane that you can’t call it the same plane. Not to mention it’s powered by two engines, not one. And secondly, the R-27 engine has a thrust double of that of the WP-13 or R-13.

read the thread

there are two R-27s and the MiG-23PD has one of only 7800kg of thrust, read before you claim any thing go back a few pages

Wow, somebody 1st got a rude translation of J10 speculation written by an anonymous Chinese as his argument Bible, then found another internet based portal as his saint source for arguing, ridiculous as I can see people avoid answering directly to the evidence harden points as raised by other members but only sought such “Bibles said “treatments :rolleyes:

How convenient, cheap tricks only make debate cheap :diablo:

Read the thread i have answered all of them, you simply go over and over answering your self without reading use reasoning buddy, the WP-13 was the only engine availiable at the time, re engine is possible, the MiG-21 can achieve mach 2 with R-13s, the J-10 is a light aircraft even lighter than a MiG-23 powered by a R-27.

You power the F-16 with F-100 not because of speed but because of range, payload and agility.