Mallard CSM-W: Command module orbiter with deployable wings!

[Jamie Logan]

Hello!

Today, I've got a new toy.

Everyone has made a basic orbiter with command module return capabilities, usually using the trusty ol' heat shield and parachutes, but I decided to try to build an orbiter that can land using a set of extendable wings, much like one of the proposals for the Gemini Program:

 

 

Introducing the Mallard CSM-W:

 

 

The Mallard CSM-W is a standard LKO crew module. The launch vehicle can place the orbiter into an equatorial LKO, and the orbiter has a few hundred m/s of on-orbit maneuvering fuel. The orbiter also comes with RCS thrusters, fuel, and a forward mounted port to allow for rendezvous and docking. The service bay behind the command module has two sets of wings with landing gear folded in at launch, which can be deployed prior to de-orbit and re-entry.

Upon re-entry, an initial angle of attack of 90 deg will allow you to bleed off enough speed to keep temperatures low once you reach the lower atmosphere. Once you kill the majority of your speed, you'll need to look to land quickly since the lift-to-drag ratio is pretty poor. I've found it to be easiest to simply dive down to maintain airspeed, and then level off just before you reach the ground. Landing works best around 60 m/s, as it's decently slow but still above the stall speed. It can be landed on the KSC runway, or really anywhere else with sufficiently flat ground. Dumping the remainder of your maneuvering fuel before landing is also recommended.
 

Action groups:

AG1) Toggle lock on all robotics parts (locked by default at launch)

AG2) Deploy wings and gear

 

When deploying the wings, first use AG1 to unlock the robotics, then use AG2 to deploy. Once the wings are deployed, use AG1 again to re-lock the robotics parts. This is critical, as the wing parts are autostrutted to the command module, and will be unstable if not re-locked. Due to what I assume to be a bug, re-locking the robotics parts does not always work for all of them (usually the tiny hinges) so you'll have to check all 12 of them to be sure they are re-locked before re-entry. The game will display the "Cannot Lock Robotic part, Servo is moving" warning, even though none of them are still moving after being deployed. Not sure why this happens, but manually locking the rest of the parts does not take long.

 

Here is a lovely gif of the wing deployment in action: https://i.imgur.com/257oimq.gifv

 

Craft file: https://kerbalx.com/Jamie_Logan/Mallard-CSM-W

 

Gallery:

 

 

 

I hope you enjoyed it! Here is my last post:

 

Edited June 8, 2020 by Jamie Logan

[Cavscout74]

Nicely done!!!!  I'm gonna have to try it out

One tip for the unlocking/relocking of robotic parts:  Due to some of them usually not working as desired, it's often best to use 2 actions groups - one unlocks all, the second locks all rather than using the toggle.  That way, any that don't lock you just hit the lock AG again rather than searching out which part generated the " Cannot Lock Robotic part, Servo is moving" message.

[Jamie Logan]

1 hour ago, Cavscout74 said:

Nicely done!!!!  I'm gonna have to try it out

One tip for the unlocking/relocking of robotic parts:  Due to some of them usually not working as desired, it's often best to use 2 actions groups - one unlocks all, the second locks all rather than using the toggle.  That way, any that don't lock you just hit the lock AG again rather than searching out which part generated the " Cannot Lock Robotic part, Servo is moving" message.

Thanks for the tip, I'll give it a try with this vessel.

[sturmhauke]

This is cool stuff! I've messed around with folding vehicles of various kinds, but nothing as compact as this.