Delfin
Forista Sancionado o Expulsado
Los M-88-2 o los M-88-3?
"Originally there were 2 steps for thrust increasement proposed. The M88-3 was proposed to offer 20 % more thrust (60 kN EN SECO / 90 kN con POSTCOMBUSTIÓN). In a second step the M88-4 was to offer a RH thrust of about 11000 kg, dry thrust was not disclosed.
Snecma tested a kind of M88-3 prototype in february 2005 for the first time and AFAIK they achieved the intended thrust, though I'm not sure.
Meanwhile Snecma offers the M88-2ECO it's more a technology demonstration programme. New hardware is installed on the M88-2 (older modules being replaced with them). The modules are fully exchangeable so that you can retrofit any older M88-2 with the new hardware.
The improved engine offers the customer 2 options:
1) 20 % with same life cycle
2) Same thrust (50 kN dry/75 kN RH) with increased life time"
"The M88-2,5 or 2+, whatever you name that engine has thrust-level of M88-2 and an increased life-time through components intended for M88-3.
We keep in mind, that the FADEC allows high-thrust-levels in wartime, by trading life-time against thrust at all.
In daily operations and even in wartime, the present thrust levels are sufficant. A Rafale is in low level flight restriced to 500 kt TAS through its automatic tarrain mode at all. With external loads it will not go behind 600 kt higher-up. So in dash before attack and the escape run, you have to go into burner and the related fuel penality by that. If you do that with 75 kN or 80 kN engines brings a very small time difference of a few seconds at best in accelleration, but no savings in fuel consumption. Extra power has to be paid for in some way. The Rafale was designed for best performance ratios around 75 kN engines. (fuel-ratio, thrust-ratio and flight performance from that!)
Higher thrust level are a marketing argument by several engine producers, but in reality not used in daily operations. The EJ200 surpasses 100 kN, but is kept by ~90 kN. Sometimes you do not feel the extra power, because it is not linear or restricted by other limitations.
What we do not know is the behavior of the M88 in operations. A smooth constant rise in power is more usefull, like an erratic behavior, what delays the Indians with its Kaveri. No engineer can ashure that and you are in need in a lot of luck and experiences with engines to achive that.
We compare numbers, which do not show the true nature of an engine. The engine by the way shows different behavior, when installed in different inlet-outlet-systems. What does work well till ~75 kN do not so at ~80 kN.
To optimise it to the higher thrust level too, you have to invest new money. Most customers are not convinced by the gains from that. A better EW-suit or better weaponary seemed to be a better investment, when it comes to gains from that. If you are in need of some extra kN for short periods, the FADEC will do the job. In wartime the life-time of an engine is of much lesser importance. Up to 10-20% extra power is possible by that. For the M88 it is to the lower side, because it operates close to heat limit for good sfc at all."
Otra opinión:
"false yet, the max output of the EJ200 is 89kN, sources RR!"
