Most expensive military project failures

[Zanza]

Airbus A400M as a non US project that went way over budget with poor outcome.

A nice anecdote for a failed military project may be the renovation of the German tall ship Gorch Fock. Takes years and is hugely over budget.

[Tonitrus]

The ACU uniform, whose camouflage only worked if you were trying to hide in a gravel pit.  Whatever procurement officer signed off on that must have gotten a nice consulting job with the manufacturer afterwards.

And we USAF folks followed you guys right into that gravel pit...but at least we had chosen sexy tiger stripes. 

[The Brain]

Redundant much?

[Richard Hakluyt]

I'm fairly sure that Ed Anger would have found a way to get Montgomery into this thread 

[The Brain]

I'm fairly sure that Ed Anger would have found a way to get Montgomery into this thread 

But not into Caen.

[Duque de Bragança]

I'm fairly sure that Ed Anger would have found a way to get Montgomery into this thread 

But not into Caen.

Nor Arnhem.

[Berkut]

Is the F35 a true failure, or just much more costly and functional than most countries want/can afford right now?

Honest question.

It's still under development (even as it is under production, which is by itself kind of insane) so maybe they'll be able to pull a rabbit out of a hat, but it seems like it's going to be a failure. 

How is that insane? I can't think of a single combat aircraft since WW2 that was not under development while it was under production. For that matter, most weapon systems work that way - I am inclined to even say all of them, but I imagine there are some exceptions that would make "all" technically incorrect.

[Brazen]

Thanks, everyone! Writing this up this week, I've got a few choice expert comments too. Navy programmes seem especially prone. I'll posta link for you to criticise everything I got wrong when it's published next month