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Somewhere in the shuttle design is a lesson about not cramming too much into the MVP. Many years ago, in some high school engineering camp, I remember a univer

Somewhere in the shuttle design is a lesson about not cramming too much into the MVP. Many years ago, in some high school engineering camp, I remember a university professor who had been involved in the STS design talking about feature creep in the shuttle program in very uncomplimentary terms. According to the prof, the shuttle as originally envisioned would have had about 1/2 the cargo volume, and less throw weight, but in return a higher orbit at engine cut-off, much better serviceability, and a simpler design. In order to get the support of the military, the cargo requirement was pushed to what was just-barely-heroically-possible engineering in order to launch the military satellites desired by the spooks. This decision compromised the program in every way imaginable. The schedule stretched out. The launch-pad weight ballooned, forcing the solid booster design into barely-possible territory. The original goal of "recycle for weekly launches" became a pipe dream. The re-entry heat shield design became very complex. The unit cost ballooned. The cost per launch ballooned. The right answer all along would have been to tell the spooks: "No, damn it, design satellites that fit the payload bay or take a hike." The spooks would have had many years to refine and compact ever-better satellites. We paid a high price for poor program management decisions at the top. The lesson I take out of it: As engineers, we need to think about risk budget at all times. Pushing the envelope on something is probably necessary to beat the competition. Pushing the envelope on everything is poor risk management. As an engineering manager, be very intentional about where risk is allowed. Concentrate your management efforts on de-risking the risky, and delegate the low-risk to clear your mind for managing the unpredictable. I will admit that I have not always done that, and have collected the scars that I deserved.

trhway 8y ago
Regarding the feature creep Pentagon Wars come to mind :) Another answer is modularity of design, like Falcon Heavy. Though granted it is much harder for a spaceplane concept and may as well be an ultimate feature creep.
sgt101 8y ago
You have to have a lot of power to do that. In most cases you'll just be removed.
nradov 8y ago
In the end, feature de-creep turned out to be a bigger safety problem than feature creep. The early STS design proposals called for a titanium airframe which could have withstood reentry temperatures. But to reduce costs and speed up manufacturing they switched to an aluminum airframe covered with ceramic tiles. Those tiles were fragile, leading to one crash and several near misses (like this article). https://history.nasa.gov/SP-4221/ch8.htm https://history.nasa.gov/SP-4221/ch8.htm Also the performance of spy satellites is dictated by optics. In order to get sharper images you need larger lenses. That's just physics. Smaller will always be worse.

trhway 8y ago

Regarding the feature creep Pentagon Wars come to mind :) Another answer is modularity of design, like Falcon Heavy. Though granted it is much harder for a spaceplane concept and may as well be an ultimate feature creep.

sgt101 8y ago

You have to have a lot of power to do that. In most cases you'll just be removed.

nradov 8y ago

In the end, feature de-creep turned out to be a bigger safety problem than feature creep. The early STS design proposals called for a titanium airframe which could have withstood reentry temperatures. But to reduce costs and speed up manufacturing they switched to an aluminum airframe covered with ceramic tiles. Those tiles were fragile, leading to one crash and several near misses (like this article). https://history.nasa.gov/SP-4221/ch8.htm https://history.nasa.gov/SP-4221/ch8.htm Also the performance of spy satellites is dictated by optics. In order to get sharper images you need larger lenses. That's just physics. Smaller will always be worse.