that’s exactly my point. Those engines are incremental improvements on existing designs from the 1970s and 60s - hence why you will find this tech in western museums. There have been improvements - certainly - and the engines are now made almost entirely in India but the original point stands - the designs are not indian hence why we should temper our expectations of where Indian aerospace can go. They currently occupy the niche of cheap space launches and that is based on excellent work by ISRO and their partners.
That's a valid argument but still a bit strange. One could make the same argument about:
- chip design - modern processors are not fundamentally different from 8086, which also belongs in a museum. Sure, there's much higher transistor density and advances like pipelining, branch prediction, multiple cores etc. but fundamentally it's still the same physics and design.
- machine learning - aren't modern deep networks just scaled up versions (with some new architectural components although one can argue that even these were discovered in the 80s and 90s) of old ideas that still use gradient descent and backpropagation. this too sounds like incremental progress.
- commercial aircraft - aren't modern planes just incremental advances of 50-year old planes (the 747 is from the 60s). sure, they are more efficient, use lighter composites etc.
I guess my point is that either (a) technology as a whole has been making incremental progress when viewed from a certain lens, or (b) that while, superficially, a lot of technology still follows designs discovered decades ago, there have been substantial and deep improvements at various lower levels of the "stack".
Maybe a concrete way of looking at this particular issue would be to compare metrics like efficiency of the engines (is amount of thrust * time thrust was produced for / amount of fuel used = change in momentum / amount of fuel used, a useful metric?) or just raw amount of thrust produced? Then one could argue that an engine is essentially still the same as ones from a few decades ago.
Your thrust argument is borne out in the time it takes indian rockets to reach lunar orbit compared to even the USA’s saturn rockets from the 60s - a week in 2022 versus hours in 1970.
I’m not sure your comparison makes sense. The ability to develop chips is what i’m pointing out. That does not exist everywhere and developing that today is a monumental task. This is why chip design is limited to a few countries and fabrication to even fewer ones.