[ianbicking]

I noticed that too. That seemed odd at first read... after all, it has a guidance system, it's not relying on exact aim. I'm assuming it's more that its guidance system can only has so much fuel at its disposal and ability to correct errors, and if it's aimed incorrectly it would exhaust its fuel before it corrects its trajectory.

[ethbr1]

Sometimes it's less work to engineer a hard problem into an easy one, than to solve the hard problem.

Most of the tech for the Minuteman I was developed in the mid-1950s.

With that level of processing, would you rather solve a 2d problem by precisely orienting the missile before launch? Or a 3d one by requiring it to orient during flight?

Keep in mind: any equipment to self-orient in-flight also needs to be carried on the missile itself, while being tolerant of launch, acceleration, and reentry forces.

Any precision machinery at the launch site has no such requirements.

[aeonik]

This doesn't make sense to me. I would assume the engines starting by themselves would introduce enough error to throw the entire system off. Let alone natural seismic events in the ground, plus wind.

I would guess you must solve the 3D problem at least to some degree.

[ethbr1]

I'm not a rocket scientist, but I think thrust is pretty constant at that scale. That's why they start, spool up, then release from cradle.

Vs something like a Polaris SLBM that has a much more variable guidance problem

It'd be curious to see how early ICBM and SLBM guidance systems differ.

[kens]

I haven't looked at submarine systems in detail, but my understanding is that the big problem is that an ICBM knows where it's starting, but the submarine travels. So submarines have super-accurate inertial navigation systems on board to determine their position.

[ethbr1]

I was thinking more for the sequence where it broaches the surface then lights its engine.

https://m.youtube.com/watch?v=h5KejRbD5s0&t=34s

That's a lot more dynamic of a launch orientation. Which way is it rotated? Is it inclined off vertical?