I almost skipped the videos embedded in this article, but they are well curated gems. A few tidbits I found amazing:
- 800°F (and above) was the temperature of their cooling air
- the engine ran too hot for electronics, so they designed a hydraulic mechanical computer responsible for regulating various inputs
- the roar from the two external 400 cubic inch Buick V8 engines originally used to start the aircraft was so irresistible to the hotrod enthusiasts running them that they sometimes neglected to disconnect in time before the starter engines overran RPM limits and "puked their guts out under the airplane" - they had to buy up so much replacement stock as to deplete every single junkyard across the USA of that particular model (so the story goes - probably hyperbole but a fun tale!)
I remember quite well the day the auctioned off a unique "jet fuel analyzer" that was used to do some of the specialized testing for these exact aircraft.
It was not a benchtop unit, it was a forklift model :\
A handful of the surviving planes are in museums. If you're at all interested in aviation and have the chance to see one, do. There's something special about them that doesn't come across in pictures.
In the 90s, NASA refurbished and extensively modified a mothballed supersonic Soviet-era Tu-144. The modifications included fitting different (Tupolev) engines. The total cost was $350M. It was used as a flying laboratory.
Guessing this project was also a way to pay Russian engineers while the Soviet Union collapsed with the goal to do "technology transfer" and prevent them from working for NK and the like as a way to make ends meet.
Yep. After the collapse of the USSR, the US Congress and NASA funded the International Space Station program in part to keep Russian rocket scientists gainfully employed. That way they wouldn't be tempted to go work for Iraq / Iran / North Korea / China.
When I see this, I can only think of modern high-altitude balloons. My gut tells me the SR-71 would be an ideal interceptor for that new threat (despite not being an interceptor itself).
The balloon issue cannot be addressed by any modern US aircraft, and spending expensive missiles on low cost balloons seems like wasting money and resources.
The SR-71 was never designed as an interceptor, and would require extensive modifications to carry and employ weapons. Not going to happen. There was an earlier YF-12 interceptor program but it never proceeded beyond the prototype stage.
High-altitude balloons are hardly a new threat. They have been used for decades, although some recent Chinese models are more capable than before. Regular tactical aircraft already in the US inventory are perfectly capable of shooting them down.
The service ceiling of the SR-71 is still well beneath the altitude of a modern balloon. The speed isn't necessary, and it's altitude record has been beaten by other modern jets.
If we're spitballing solutions, balloons are slow, fragile and move in relatively predictable paths. An F-15 could reach the same altitude, and launch it's own balloon with a small solid-fuel booster that also corrects the trajectory. If the interceptor balloon could get within 1-2km of the target balloon, then a cheap kinetic weapon firing HEI projectiles might be enough to destroy it.
- 800°F (and above) was the temperature of their cooling air
- the engine ran too hot for electronics, so they designed a hydraulic mechanical computer responsible for regulating various inputs
- the roar from the two external 400 cubic inch Buick V8 engines originally used to start the aircraft was so irresistible to the hotrod enthusiasts running them that they sometimes neglected to disconnect in time before the starter engines overran RPM limits and "puked their guts out under the airplane" - they had to buy up so much replacement stock as to deplete every single junkyard across the USA of that particular model (so the story goes - probably hyperbole but a fun tale!)
[0] https://www.thesr71blackbird.com/Aircraft/Engines/starting-t...
It was not a benchtop unit, it was a forklift model :\
NASA asked several former SR-71A staffers to help secret restart - https://news.ycombinator.com/item?id=49890733 - Sept 2026 (401 comments)
The balloon issue cannot be addressed by any modern US aircraft, and spending expensive missiles on low cost balloons seems like wasting money and resources.
We'll know soon.
High-altitude balloons are hardly a new threat. They have been used for decades, although some recent Chinese models are more capable than before. Regular tactical aircraft already in the US inventory are perfectly capable of shooting them down.
https://www.af.mil/News/Article-Display/Article/3288579/f-22...
If we're spitballing solutions, balloons are slow, fragile and move in relatively predictable paths. An F-15 could reach the same altitude, and launch it's own balloon with a small solid-fuel booster that also corrects the trajectory. If the interceptor balloon could get within 1-2km of the target balloon, then a cheap kinetic weapon firing HEI projectiles might be enough to destroy it.