Bossart I
by gc1ceo
uploaded 2019-01-04
(updated 2019-06-06)
mod ship
#bossart #atlas #AtlasI


  • Type: VAB
  • Class: ship
  • Part Count: 41
  • Mods: 3


  • Bluedog DB
  • Squad (stock)
  • TweakableEverything

The Atlas rocket family began in 1959 with the launching of the first Atlas launch vehicle and within just a couple of years had become the primary heavy lifter for the American space program. The first generation of Atlas rockets were responsible for launching many important payloads both into orbit including most of the Mercury program, as well as landing the first soft-landing of an American probe on the lunar surface.

The powerful Centaur upper stage was initially developed exclusively for the Atlas rocket as it used many of the same technologies including its stainless steel extremely thin balloon tanks allowing for a high ratio between wet and dry mass. It was first used towards the end of the first generation of Atlas and continued as a successful combination into Atlas’ second generation which saw lengthened fuel tanks, improved avionics and bolder interplanetary missions.

A third generation of Atlas rockets was developed to continue as a dependable lifter for both civilian and government payloads. It was a continuation of the same principles that had led to the second generation with a simplified and lighter Centaur D and continued improvements in avionics for both vehicles. The result were three variations starting with the Atlas G which first launched in 1984 with four successful missions, the Atlas H which was the same rocket minus the Centaur, and lastly the Atlas I which was a re-branded version meant for civilian payloads used from 1990 to 1997.

The Bossart I is the Bluedog Design Bureau’s version of the Atlas G/I and is essentially the same rocket as most of my previous Bossart builds with additional fuel tanks. It still uses a stage-and-a-half design with the booster stage ejected somewhere in the upper atmosphere.

The Inon D is Bluedog Design Bureau’s version of the Centaur D which with its avionics also approximates the Centaur D-1A which is a powerful upper stage meant to carry larger payloads in excess of 2 tonnes to KSO (Kerbal Synchronous Orbit) or beyond. It uses cryogenic fuels so depending on your setting may experience some boil-off – it isn’t meant to sit around for very long between burns.

The ascent procedure can vary depending on the mission and is a bit different whatever you are looking for a parking orbit, transfer orbit, or a direct ascent. The sustainer and booster engines are fired together with the booster engines decoupled around the time the rocket enters the upper atmosphere or as late as 30 seconds before complete depletion. The Bossart either burns to exhaustion for a higher orbit or direct ascent or is prematurely shutdown upon reaching your parking orbit altitude.

A parking or lower orbit will probably leave you with enough fuel to complete the orbital process, or at least complete most of it thus leaving the Bossart as orbital debris. A higher or transit orbit will probably see it exhausted in which case the depleted Bossart will eventually re-enter the atmosphere. A direct ascent will see it put into a highly elliptical orbit or a crash trajectory with your target body.

The Inon D will either be used to continue a direct ascent, help to establish a parking orbit, or circularize a transit orbit. There is more than enough fuel to complete most missions and will probably be in excess in the majority of cases.

I have included a test payload, a 2 tonne keosynchronous communications satellite meant for a launch to KTO (Kerbin Transit Orbit) at 2,863.33 km meant to be a third or fourth generation communications relay. It can be substituted for any payload of roughly the same mass and dimensions.

Built in the VAB in KSP version 1.7.1.

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