I think I have an idea for a really good engine? I don’t know it might be that I am just hungry but just bare with me if it is actually an idea.
The jet engine has a really powerful laser powered by a nuclear reactor in the 747-400, the laser is refracted to the engines on the outer wings via the inside of the wings. The Laser is hit against a focus point and the air there is super heated to a plasma, the super heated air is forced through the engine maybe like a ram jet or something?? The laser is turned off and new air is sucked in and then the laser is turned back on for a split second, the same process repeats itself.
PerfectDark, what are you reading? Between this, your submarine aircraft carrier and the vacuum/maglev train, you’re either a technological visionary or have a comprehensive sci-fi collection.
…and sorry to be a wet blanket, but no airline or government in the world is likely to sanction nuclear reactors in commercial jets for the foreseeable future. One plane crash and you’ve irradiated an entire airport and the nearby city! (Plus the inevitable development and construction cost issues - how heavy is a reactor, anyway? - prove it’ll save money and get past regulators and someone will show an interest, otherwise forget it)
Can’t comment on the technical feasibility, sorry.
The problem with lasers – especially Big, Powerful Ones that can perform the sort of air breakdown you’re talking about, is that they are shockingly inefficient. Only a couple of percent (at best) of the energy used up shows up as laser light. The rest goes up as waste heat. It’s going to get HOT in that jet of yours, even if you roll down the windows.
Trust me – I’ve worked on Laser Propulsion at a Research Lab. No joke.
Actually, there is a guy working on this right now, with a moderate degree of success – his name is Leik Myrabo (pronounced “Lake Mirabo”, as if it’s a geographical feature in East Arica)at Renssalear Polythechnic Institute in New York. The only difference is that his Apollo Laser Lightcraft doesn’t carry the laser with it – that stays on the ground. He coauthored a book on the topic with sf writer Dean Ing. (Dean Ing went on to write a novel based on the ideas titled The Big Lifters. The idea is very different from the laser propulsion ideas of Arthur Kantrowitz, which showed up in Jerry Pournell’s “High Justice” or Michael Kube-McDowell’s “The Quiet Pools”. But I digress.)
The US Air Force looked into developing nuclear-powered aircraft in the 50’s. It was feasable, but due to the weight of the powerplant, the aircraft wouldn’t have been able to carry any payload, just the pilot. Not even close to being worth the trouble.