Most noodle-like (highest aspect ratio) orbital launch vehicle ever?

Question

• Just how much can tall skinny rockets bend? (roughly, safely)
• Why is Falcon 9's shape so tall and skinny?
• If not constrained by underpasses, etc., would Falcon 9 have been less of a flying noodle?
• What determines rocket height/width?
• Smallest orbital rocket by diameter? (currently unanswered, could be this one)
• Smallest orbital rockets by height?

are well and good, but after seeing the Scout D-1 in the excellent Curious Droid video Black Arrow : The Lipstick Rocket - A Very British Space Program at around 09:33 (screen shot below) where it looks as thin and tall as the metal towers holding the lightning wires around the launch site I wondered if this is in fact the highest aspect ratio (height/width) or most "noodle-like" orbital launch vehicle ever.

Question: What is/was the most noodle-like orbital launch vehicle ever? Which one has/had the highest aspect ratio? Don't including fins, strap-ons or fairings, just the rocket body diameter. If it's modulated along the length, feel free to take some length-averaged mean diameter if necessary.

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From If not constrained by underpasses, etc., would Falcon 9 have been less of a flying noodle? illustrating that rockets can be so long and narrow that they can bend and flex in the wind!

Answer 1

For simplicity, I will go with the ratio of height to largest cylindrical diameter. That should be an okay definition of "noodly".

This is the result of going through all the all-solid orbital launchers I could find, since none of the liquid ones were even close.

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To start out, let's check your Scout-D.1 suspicion:
Scout D-1: 25m : 1.14m = 21.93, as a starting point.

But there were many versions of the Scout, and going through all of them, the following ones were more "noodly" than the D-1:

• Blue Scout II: 24m : 1.02m = 23.52
• Scout B: 25m: 1.01m = 24.75
• Scout X-1: 25m: 1.01m = 24.75
• Scout X-2: 25m: 1.01m = 24.75
• Scout X-3: 24m : 1.02m = 23.76
• Scout X-4: 25m: 1.01m = 24.75

I couldn't find anything better, but here's a selection of others:

Even with their noodly reputation, none of the Falcons are above 20:1

SLV is pretty noodly, but 22m : 1m = 22 isn't good enough to beat the scouts.
ASLV: 23.5 m : 1m = 23.5, but that may or may not count as it had boosters.

Lambda 3 17.4m : 0.74m = 23.51, very close.

Scout X-2