[tpmx]

Tangential, sorry. In the 70s/80s I grew up ~1.5 km from a Swedish Air Force Base's runway (located in the middle of nowhere, near our tiny "city" of 5k people) equipped first with Draken and later Viggen aircraft. Our kitchen was ideal for watching takeoffs.

It was a very common thing to see a few them take off in the morning during breakfast just before going off to school. Especially Draken made such a glorious sound when taking off:

https://www.youtube.com/watch?v=j7L7_3cwptk (remind yourself that this is a 1955-1959 aircraft when you see it taking off)

[Terry_Roll]

In the early 00's when on holiday, something made me look up at the clear blue sky and I saw what can best be described as a control which looked like button mushrooms laid top to bottom one after the other.

Fast forward to now and its likely I saw the contrail of an aircraft with a scramjet This is like what I saw but there was a gap between each button mushroom. https://files.abovetopsecret.com/images/member/a2712a44ce6c....

Some call it doughnuts on ropes which might be something called pulse detonation?

[jacquesm]

It really needs those little wheels at the end of the fuselage to avoid a tailstrike.

[tpmx]

Looks like it has them. You can see them being "folded in" at 1m07s.

[jacquesm]

Yes, I was commenting on those. The fact that it has them and really needs them. Those things aren't optional, if you look at the take-off you can see them keep the tail safe.