A Naval Fighter is fundamentally different from an Air Force Fighter. Its entire structural frame needs to be designed and built to handle the harsh conditions of carrier landings. That adds extra weight, which isn’t necessary for Air Force fighters. This means the AMCA and the N-AMCA will have entirely different airframes. You can’t simply modify the AMCA into an N-AMCA or vice versa. It’s possible, like with the Rafale, but we can't afford the delays that come with that approach. What we desperately need right now is a dedicated Air Force fighter.
I get what people are thinking when they talk about the N-AMCA. They’re imagining a fifth-generation fighter jet with an internal weapons bay. But let me point out that the only operational fifth-generation fighters with such a bay are the F-35 and the upcoming J-35.
Now, let’s talk payloads. When it comes to a naval stealth fighter, unless you’ve got engines with enough dry thrust like the F-135, you can’t design a large, voluminous internal bay for a twin-engine setup. The underbelly will end up with a shallower bay because of the intakes on either side. To make the bay large enough, you’d either need slimmer engines or a beefier plane—which adds even more weight.
Unless you’re planning to field a naval air superiority fighter on its own, you first need a solid baseline naval strike fighter. Look at examples like Rafale for strike roles leading to FCAS for air superiority, or the F-35 paving the way for NGAD in the same role.
Fighter payloads meant for anti-ship roles are heavy and have large diameters, like the BrahMos or LRASM, rather than being long like air-to-air missiles. So, depth becomes critical. With the engines we currently have, it’s just not feasible to design a stealth naval strike fighter capable of carrying such heavy payloads internally. At best, we’d end up with a naval air superiority fighter like the J-35 if we try to make the AMCA stealth-capable for carrier operations. But that type of aircraft can’t serve as the backbone of our fleet. Right now, our carriers are practically useless without proper platforms. The priority has to be fielding a decent naval fighter within a reasonable timeframe. It doesn’t matter if we eventually get an N-AMCA—it’s not going to carry a BrahMos internally let alone medium size payload like a LRASM/JSM, is it?