Gripen is unlikely to need it as the RM12 already use a larger fan than the F404.

err, the F404/RM12 has the SAME fan dia. as the F404/F2J3 from which the F404/IN20 has evolved. What are you going on about?

Here are the specifications of both from http://www.geae.com/engines/military/comparison_turbofan.html

RM12 ::: F2J3

Fan/Compressor Stages: 3/7 ::: 3/7
Low-Pressure Turbine / High-Pressure Turbine: 1/1 ::: 1/1
Maximum Diameter (Inches): 35 ::: 35
Length (Inches): 154 ::: 154
Dry Weight (Lb.): 2,325 ::: 2335

Power Specifications
Specific Fuel Consumption at Maximum Power: 1.78 ::: 1.8
Max. Power at Sea Level: 18,100 ::: 18,300
Overall Pressure Ratio at Maximum Power: 27 ::: 27

Robban,

Here are some reasons how instantaneous turn rate is affected.

1. Velocity
2. Weight
3. Wing loading
4. Altitude

The lower the velocity the faster the turn rate. This is observable even when one drives ones car. The slower it is the quicker it will turn.

Wing loading effects how quickly the aircraft can turn.

Weight effects corner velocity.

Altitude = air density and air pressure, which in turn effect the lift:drag ratio, which in turn effect corner velocity, which directly effects Instantaneous Turn Rate (ITR).

Corner velocity is the minimum velocity at which the maximum g rate can be attained. This is when the aircraft is the most manoeuvreable.

Anyone who makes a statement about turn rates should also be able to state the conditions under which such a manoeuvre is being observed. Further if you want to compare 2 airframes then you should be able to state that the results are based on similar conditions. As conditions change so will the observed results.

Most times, people forget to evaluate the conditions under which such comparisons are made. Such comparisons are a waste of time.

This is the reason I put together an excel worksheet. BTW I am not an expert, simply someone who put together formulas which are available in the public domain in one convenient worksheet.

If you want to compare the Gripen and the Tejas, I am willing to listen to your figures and debate them mathematically. But if you do not want to be dismissed as someone simply repeating marketing blurbs you should state conditions under which such results were observed. Without this your statements about turn rates hold no water.

In the meantime I stand by what Joey wrote up-thread, except to add the turn rates quoted are ITR and not sustained turn rates (relevant corner velocities as also other conditions are also provided in the same quote).

Kilocoo316,

Assuming the rotation performed by the ski jump is the only effect is a fundamental error. While it does perform a rotation – unlike in normal non-ski-jump-assited takeoffs – ground effect performance is not decreased. Hence it does a lot more than only induce rotation or impart ‘vertical speed’. It increases lift efficiency AND maintains the same low drag due to ground effect.

This is no small matter, drag reduction due to ground effect has been calculated to be about half as without ground effects. IOW during a normal takeoff the moment a rotation is performed drag effects double, a ski ramp maintains this low drag effect alongwith the increase in lift.

No offence taken. But I feel I must point out some things which you have missed in my post, and have repeated again.

1. The last statement I made was “Thats my opinion – take it FWIW.” You are free to express your own opinion as you see it.

2. Experience gained is never lost. That is a fundamental misconcpetion. A deck crew chief has spent his life on the carrier, there is no other place for him to go. His eventual replacement started as a deck hand and will replace him. Along the way he has absorbed the crew chiefs knowledge and added some more of his own. He will pass this to his successor and so on. Thats how experience is passed on in real life. The navy is already training the next crew chief once a new one is appointed. I fail to see how this continuity of experience can ever be lost? This is the case with officers too. It would be foolish for any navy to wait for a crew member to retire before training his/her replacement.

Furthermore on the one hand while you accept there is an knowledge gap which may take ~3-10 years to cover (which is what I said more or less), but on the other you say “Knowledge is recorded in manuals, and manuals can be bought”, thereby implying such knowledge can be gained and instantly applied to carrier operations by talking to others, instead of gaining it for oneself.

…Crews come and go with time, and experience is lost with the men, knowledge is not. Knowledge is recorded in manuals, and manuals can be bought…

…

To sum up, just because the PLAN have not operated carriers before does not mean that they can’t learn from others instead of trying everything in-house and doing everything the hard way. And any operational experience gap between the two sides would disappear pretty quick once a carrier is in operation. So any noteworthy difference in crew quality between the PLAN and IN in terms of carrier ops will only last for a fairly short period of 3~10 years.

I’m really not sure what the thrust of your debate is? If you have already conceeded to the gap and agree that it may take ~3-10 years to catch up, aren’t you more or less in agreement with my post?

As regards proponents of the IN, I really don’t take this as a mine is bigger than yours. Its my opinion – feel free to disagree.

…Shalav..I dont care that Agni is of Stealth/MRV capable..india should go on..and more..they will hurt themselves..Like Pakistan..because nobody is going to use it…same is with Iran ar such crucial stage ..they are testing missiles all the war mongring…by both sides..

I don’t care either! I thought your statement about it “resembling an Agni” meant you had some insights. Apparently its just hot air. So lets just stick to talk about the Iranian missile.

Thats a nice conception. The only (minor) thing that spoils it for me is the absence of the recognizeable raked wingtips of the ‘normal’ F15.

Here’s what I think.

If you forsee any limitation with the Fuji lens then go for a SLR. The money you will spend on getting accessory lenses for the Fuji would be better spent on getting lenses for the SLR you choose.

Sensor size:
This means the physical dimensions of the sensor (not the megapixels crammed within the lenght and breadth of that sensor). This is the most overlooked aspect when purchasing a digital camera. The size of the sensor will affect the quality of the image. As a thumb rule, the larger the sensor size the better image quality. This is because larger sensors enable the manufacturer to use larger individual sensors, which means those are more sensitive to light than smaller sensors. Hence better quality of the image. In increasing order of sensor size

Fuji Fuji
Olympus E500
Canon D350
Nikon D50

Lens compatibility:
If you go for an SLR, you will eventually feel the need for a different lens than from the kit one you got with the camera. The ability to use different lenses for different situations is what makes SLRs so popular. The big daddy of backward lens compatibility are the Nikons and Pentax’s. You can use lens released 40 years ago with their modern DSLRs even today. Of-course no auto features, but you can find cheap old compatible lenses for them. Canon really muffed it when they changed their lens system from the old FD to EF. They had their reasons, but as an owner of a set of (expensive) FD lenses for my AE1 it really bothered me. However their EF and EF-L lenses are pretty good glass. Olympus opted for a 4/3rd sensor size for their digital offerings. AFAIK their Zuiko series are more expensive than comparable Canon or Nikon glass. Further no other 3rd party manufactuer offers cheaper alternatives for their zuiko lenses. For Nikon or Canon you can purchase cheaper glass from manufacturers such as Tamron, Sigma, Tokina etc…

Image processing engine:
The image processing engine which comes with the camera can vary a lot. You should compare images of similar shots taken under similar conditions at sites such as Dpreview.com

Lastly, but the most important. Your budget.

Final note:
You don’t have to be an equipment measuretubator. If a pinhole camera can give you what you want, you dont need to spend large amounts of money to get the latest and greatest SLR or digicam. Decide what you want to do with the camera. Research the capabilities of the ones you shortlist and go for it. I’m sure you will enjoy hundreds of hours pleasureable photography.

As for me – after my AE1 I used a kodak P&S for 15 years before I decided I wanted to get back to SLR photography, so I went out and bought the Canon 350D. It gives me most of what I am looking for. I didn’t need obscenely fast picture taking 2.7 FPS for upto 14 images was good enough for me. It can use EF, EF-S and EF-L lenses. The thing that decided it for me was the availability of an FD to EF converter. That meant I could use my old FD lenses. If not for that it would have been a difficult choice between the D50 and D350 for me personally.