[Stock] Jammer II / Krammer: Mun-lander spaceplanes

[DrLucky]

Hi folks,

Long time, no post!

With 15.2 out, I took a shot at constructing a stock spaceplane capable of runway landing from a Minmus surface mission.

No funny business here; it\'s a stock craft built entirely in the VAB (though I did my spaceplane testing in the Spaceplane Hangar, of course.)

I went with a two-engine plane to permit central attachment of the launch vehicle. The Minmus landing is accomplished using the trans-lunar stages attached above-and-below the plane fuselage. It lands on its \'tail\' for that part of the mission.

The first stage / booster-fest combo is inelegant but does the job. Careful staging the last set of SRBs... they tend to detonate the second set of SRBs if you light em up instantly.

There was oodles of fuel left, so I used the cross-range capability the fuel provided to pass near the KSC, and then flew the plane back to a runway landing.

Sadly I erred on the side of caution and let the vehicle run off the side of the runway rather than use the brakes, so it wasn\'t a *perfect* mission, but the plane is perfectly reasonable at taking off again, and with 4 x 150-unit tanks (the centre fuselage is empty) and 2 engines it\'s effectively a trans-continental airliner.

The plane is responsive except at high AOA, where the canards tend to weather-gauge you. Don\'t flare too hard on final!

Here\'s my gallery:

http://imgur.com/a/WyyQR#0

Sorry about the lack of early-mission pics, but this was the first real test flight and I had no idea it would work as well as it did.

Oh - I\'ll attach the craft file as I flew it, but you\'ll need to adjust the staging - move the decouplers from Stage 1 up to Stage 0 or you\'ll lose the landing stage as soon as you light it (luckily I noticed that before I staged to it!)

DrLucky

[bio138]

Dude.

Nice...

[DrLucky]

Thanks!

I think I\'m going to tweak it a bit to clean up the boosters / first stage - those are underpowered for the weight.

I\'m also going to take another look at the plane itself - I built it with an RCS fuel tank since I thought that might be required for landing, but I wound up with no RCS thrusters, so that\'s 0.9t of dead mass in the topmost stage. However I can\'t just yank it because the plane will likely become unflyable without it I\'ve found aircraft are finicky that way.

I eventually want this thing to be Mun-capable, but for that it needs significantly better delta-V (although it has delta-V to spare for Minmus), and a much wider footprint for the landing. Minmus has those lovely flat mares to land on, but the Mun nearly guarantees a sloped landing field, which would be a big toppling risk for the Jammer.

Of course in an ideal world I\'d be able to land the thing on its wheels under RCS or something, but I find it hard to control since you\'re effectively landing it on its side, and the RCS thrusters seem to have a mind of their own on planes.

Onward!

DrLucky

[DrLucky]

So I went ahead and built the \'Krammer\' - the Jammer variant for Mun landings.

As I planned, I removed the RCS tank and shortened the length of the plane. I also went back to one centre turbojet with two fuel tanks to lighten things further. After rebalancing and testing the plane, I built it in the VAB and added a booster under each of the outboard hulls. These sport landing legs for the Munar part of the mission, and provide thrust for the return trip.

Two more small boosters (LV-909 & 2 LFTs each) provide thrust for the Trans-Munar Injection burn and for descent thrust to the Mun\'s surface.

The result is a much cleaner look, and a lot more delta-v. The wider stance helped - even with the bigger footprint I snapped off one leg at landing.

In this shot, you can see the remnants of the descent boosters which I ditched moments before landing:

Ascending back toward Kerbin:

The return flight was nominal and it was a simple matter to re-enter, descend and fly to KSC for a landing.

DrLucky

(Edit: attached the craft file)