[Stock][0.15.2] ORVL-II Multi-Purpose Orbiter, Lander, Rover and Return Vehicle

[jeremymtc]

The ORVL-II is a multi-purpose and multi-stage orbiter, lander, rover and return vehicle, with a design emphasis on systems redundancy and crew survivability. The ORVL-II carries enough fuel for successive transfers to and from Minmus and Mun orbit, with the ability to land, reconfigure for use as a rover vehicle, and configure again to a launch/return vehicle.

The main ORVL-II module consists of a MKI command module, MK16 parachute, ASAS, FL-R25 RCS tank, FL-T250 tank, and LV-909 landing engine. Also present are 6x LT-2 landing struts, and 6 small gear bays in a tri-lateral placement for rover use in any orientation. 6x RV-105 RCS blocks are placed tri-laterally on the anterior and posterior - these are mainly used for transition to and from lander and rover configuration, but also come in handy for low altitude translation and general range extension. Three additional FL-T250 drop-tanks are equipped for range extension (these tanks must be dropped prior to craft use as a rover).

An additional orbital insertion/range extension vehicle stage consists of single FL-T500 and FL-T250 tanks mated to a LV-T30 engine. This unit will normally take the main module into Munar/Minmus orbit, allow for plenty of orbital correction, and perform the majority of a Munar/Minmus descent before being exhausted.

The launch system is the wildly inefficient F30 Lifter equipped with three LV-T30 engines on the central stack (18x tri-coupled FL-T500), and three individual LV-T45 thrust-vectoring boosters (each with 4x FL-T500) for easy atmospheric control. A series of RT-10 SRBs are used to aid initial liftoff. All components of the F30 system are designed for ballistic return to Kerbin after use, leaving no orbital debris. Operation of this system is very stable and forgiving using ASAS.

This vehicle is built completely from stock [ver. 0.15.2] components.

The .craft file is attached below [updated version 21-ORVL-II-F24 added]. I\'d love to hear your feedback, thoughts and suggestions on how to improve it, particularly in the case of the atmospheric lifter!

Some pictures of the lander/rover/lander transition are attached in the spoiler tags. A second vehicle is also shown with the drop-tanks still attached.

[gyro2death]

Took it for a flight, not bad at all. Works like a charm till you lose the gimbal engines, I would switch them to the inside, you won\'t notice a difference much in stability and you\'ll get much better control for fine tuning an orbit. Also you could probably cut off a row (3) fuel tanks off the center stack and still reach orbit as if you want to be debris-less you\'ll finish your circularizing your orbit with transit stage and with a good gravity turn you\'ll be in great shape (less weight also helps launch). For bonus points you can replace the non-gimbal engines with aerospike engines as they\'re flat better in every way (though some feel this is unbalanced though it weights more), if you do that you can cut another row (3 more tanks) off the top of the outer stack assuming you move the gimbal engines inward. (Note if you do this you need to move the outer stacks upwards because aerospike engines support no weight and will break if they touch the ground)

As you might imagine I\'m a bit of an efficiency nut but overall its a great rocket, I like the landing gear trick to upright the vehicle its quite clever.

[jeremymtc]

Thanks for the feedback gyro. I like your suggestions and will be giving them a test. I hadn\'t used aerospikes pretty much for the reasons you had mentioned; also was concerned about obsolescence when they get re-done. I really like the suggestion of swapping the LTV-30 and LTV-45 engines on the lifter and will be doing some testing with this. I suspect that I may not be able to reduce fueling on the central stack with the gimballed motors because of their lesser thrust, but I\'ll find out soon!

Will upload the newer variant after proving. Thanks!

[drwolf]

wow cool lander jeremymtc.

[gyro2death]

Thanks for the feedback gyro. I like your suggestions and will be giving them a test. I hadn\'t used aerospikes pretty much for the reasons you had mentioned; also was concerned about obsolescence when they get re-done. I really like the suggestion of swapping the LTV-30 and LTV-45 engines on the lifter and will be doing some testing with this. I suspect that I may not be able to reduce fueling on the central stack with the gimballed motors because of their lesser thrust, but I\'ll find out soon!

Will upload the newer variant after proving. Thanks!

Got curious so I did some test flights, if you use the aerospikes on the outside and LTV-45\'s inside you can actually cut off 6 tanks in the center (2 rows) and 3 off the outer stacks (1 row) provided you stage the aerospikes in the stage them with the second set of SRB. Because your a row short just move the winglets in to the center stack, they weigh nothing and help prvent excessive loss of thrust while you gravity turn. This gets you into a 130+km near orbit with a good gravity turn before you drop off the main launch stage which then takes only half a tank to circularize it. But this is of course being very skimpy on the launch stage fuel, you can just leave 3 (1 row) tanks more in the central stack to be safe as your build is highly redundant.

Also using LTV-30\'s over aerospikes lets you do the exact same thing but you\'ll have only around a single tank left after circularizing if you cut 6 from the center and 3 from the outside. But overall its a nice rocket, some optimizing of staging and fuel and this things pretty lean and gets a very nice lander into orbit.

[jeremymtc]

You are (and were) 100% spot-on in your observations gyro!

I tested several different lifter iterations using your suggestions, and thanks to your help I\'ve got the same basic function with 6 fewer fuel tanks, exactly as you\'ve prescribed. I\'ve currently got it set up with aerospikes on the outboard boosters, with 3 fewer tanks there. Also removed 3 tanks from the main stack and moved the LTV-45s inboard. I tested with 6 tanks removed from the main stacks and it definitely does work, but just as you mention the insertion vehicle is left with a little less fuel reserve after circularizing/stabilizing around Kerbin. I\'ve elected to go the more inefficient route to preserve that extra bit of operational range.

There is a noticeable loss of attitude stability with the gimbals inboard, but it\'s nothing major and well within the ability of the SAS to keep in check. I might still have a little asymmetry in the SRB assemblies that may be exaggerating it, still working on overall refinement.

Updated .craft file is attached below.

[princessjane]

Thanks for giving me this great idea, I created something similar and after 4 failed attempts managed to land it on the mun. I now can cruise around the mun as my heart desires