KerbalX

Details

• Type: VAB
• Class: ship
• Part Count: 24
• Mods: 3

Mods

• FASA
• KW Rocketry
• TweakableEverything

The failure of the ATV (Agena Target Vehicle) for Gemini IX to reach orbit, it exploded during ascent, led to a backup plan for the mission of Gemini IX which included the launching of a backup, albeit smaller and simpler, target vehicle called the Augmented Target Docking Adapter (ATDA). The ATDA used Agena parts but lacked the experiment bays and engines so it couldn’t be used for boosting Gemini. However an improper secure of the lanyards holding the fairings in place using tape led to the fairings not ejecting properly. This was confirmed when Gemini IX rendezvoused with it and observed what Tom Stafford called an angry alligator – the ATDA still was used as a rendezvous target twice but the docking adapter couldn’t be used.

This is my take on the ATDA although the angry alligator incident can’t be easily simulated because of a difference in fairings. It can function as a much simpler variant of the Agena Target Vehicle (ATV) but uses some Gemini thrusters and a small monopropellent engine. However even with the small engine it’s not effective as a booster and can only provide about 70-80 dV. Since it has only a fraction of the supplies of the ATV it’s effectiveness for long term missions is very limited but still can function as a practice rendezvous and docking target for any Gemini spacecraft.

The lifter is the same Atlas rocket used for the ATV with the similar ascent and circularization procedure. The booster fairings should be ejected somewhere in the upper mid-atmosphere but can be rode all the way up to orbit since the payload is much smaller. I recommend that you leave some fuel for the ATDA to bring itself to a violent re-entry; which is the intention of the inclusion of a tiny engine.

Built in the VAB in KSP version 1.4.3.