Hypersonics - A Periodic Quest

[bobbymike]

While I’m not that old, I have read, a lot on this forum, about aerospace system development in the 50s and 60s and given tech advances still wonder why everything takes so long and in this case take an additional five years to put something in the air.

Any insight from this amazing forum to help enlighten me would be appreciated.

P.s. Being “not so old” but still wanting to see things happen in my lifetime.

 

[Hanse]

While I’m not that old, I have read, a lot on this thread, about aerospace system development in the 50s and 60s and given tech advances still wonder why everything takes so long and in this case take an additional five years to put something in the air.

Any insight from this amazing forum to help enlighten me would be appreciated.

O.s. Being “not so old” but still wanting to see things happen in my lifetime.

Two things. Risk averseness is chronic in the US. It's so bad we've even seen screeching about how the government needs to "shut SpaceX down" because it's had failures along the way. Hell, it's not even their money being spent on it and failure still terrifies them. Second is just general scumbaggery. Politicians have learned they can get headlines if they crap all over someone's failure. "Oooh, that cutting edge program is spending money I want to use to buy votes", and out rolls the soap box, cameras, and compliant media. Never mind that it might be something vital to the country, "I've got to get elected next year". And that turns the risk averse into outright cowards. Few dare to push boundaries when they might end up on the nightly news. They literally almost didn't fly the last X-51 flight because, "what if we fail?" And it was the most successful of all the flights.

"Back in the day", people understood that difficult things require persistance. Sure, things still got cancelled, but it was more because they found something even better (ICBMs instead of Pluto and Valkyrie) and rarely because it was "too difficult". It's also why there are so many people who think the moon landing didn't happen. Can you imagine if the people responsible for Apollo had had today's mentality?

 

[dark sidius]

While I’m not that old, I have read, a lot on this thread, about aerospace system development in the 50s and 60s and given tech advances still wonder why everything takes so long and in this case take an additional five years to put something in the air.

Any insight from this amazing forum to help enlighten me would be appreciated.

O.s. Being “not so old” but still wanting to see things happen in my lifetime.

I think with hypersonic we are at the limit of the laws of physics we will see more reusable space plane or space craft than hypersonic reusable plane in the futur.

 

[Josh_TN]

I think mostly it comes down to system complexity, especially software. With hypersonics, we can also add in a lack of ability to accurately model conditions with total accuracy and massive requirements for testing - extreme ranges, huge tracking and telemetry issues, etc. a ballistic missile test is relatively simple in comparison. There is probably more risk aversion as well, but that really is not a driving force: almost no one pays any attention to military programs or the accidents associated with them. Costs however may also be a big factor, and those likely also scale with complexities.

 

[yeetmahboi]

Politicians have learned they can get headlines if they crap all over someone's failure.

If I may, the A-12 documents erasure. Hundreds of boxes of docs got sent to the cutter because people was afraid that someone might got hold of the whole fiasco.

 

[Calphor]

Our ability to model complex environments has decreased our speed to field systems because everyone seems to think it is “cheaper” to model it than to fly it. We then get into the paralysis by analysis loop that persists until someone puts their foot down and finally sets a deadline to make a decision. We have forgotten that in a lot of cases, it is faster to build and learn through tests in actual environments than to spend the countless hours necessary to setup and model these complex environments. We also tend to make decisions based on the output of models that are only partially based on empirical data, then wonder why the test didn’t match the analysis. We then spend even more time analyzing the analysis.

 

[Hanse]

Our ability to model complex environments has decreased our speed to field systems because everyone seems to think it is “cheaper” to model it than to fly it. We then get into the paralysis by analysis loop that persists until someone puts their foot down and finally sets a deadline to make a decision. We have forgotten that in a lot of cases, it is faster to build and learn through tests in actual environments than to spend the countless hours necessary to setup and model these complex environments. We also tend to make decisions based on the output of models that are only partially based on empirical data, then wonder why the test didn’t match the analysis. We then spend even more time analyzing the analysis.

Yep. Compare the time frames, cost, and accomplishment for SLS and Starship.

 

[Josh_TN]

Yep. Compare the time frames, cost, and accomplishment for SLS and Starship.

False equivalence, on top of using a single datapoint and extrapolating to infinity.

 

[yeetmahboi]

Our ability to model complex environments has decreased our speed to field systems because everyone seems to think it is “cheaper” to model it than to fly it. We then get into the paralysis by analysis loop that persists until someone puts their foot down and finally sets a deadline to make a decision. We have forgotten that in a lot of cases, it is faster to build and learn through tests in actual environments than to spend the countless hours necessary to setup and model these complex environments. We also tend to make decisions based on the output of models that are only partially based on empirical data, then wonder why the test didn’t match the analysis. We then spend even more time analyzing the analysis.

The most important thing with simulations is that we improve on their fidelity eventually, ONLY through real life testing through which outputs can be analysed and fed to the sims. An over-reliance on sims not only reflect short-sighted profit-based decision makings, it hints at arrogance also.

 

[Calphor]

The most important thing with simulations is that we improve on their fidelity eventually, ONLY through real life testing through which outputs can be analysed and fed to the sims. An over-reliance on sims not only reflect short-sighted profit-based decision makings, it hints at arrogance also.

I would be carefully assuming that it applies only to contractors. In my experience, the Gov’t customer is as enamored, if not more so, than the contractor. There is a general belief within the Gov’t that simulations have progressed to the point that they are as useful, if not more so, than actual tests. Sims are intoxicating because you’ll get an “answer” without having to build and test.

 

[Hanse]

I would be carefully assuming that it applies only to contractors. In my experience, the Gov’t customer is as enamored, if not more so, than the contractor. There is a general belief within the Gov’t that simulations have progressed to the point that they are as useful, if not more so, than actual tests. Sims are intoxicating because you’ll get an “answer” without having to build and test.

And then, when they actually go fly (or try to), they see what that answer was worth.