Firefly Launch System (FLS): Vertical-take-off SSTOs!

Stratzenblitz75 · December 1, 2015

Greetings! (Also, first post on the new forum!)

Today, I present something that has taken a surprising amount of my time to develop: the Firefly Launch System. The goal behind this system is to provide a vertical take-off jet-powered SSTO that can be scaled up to lift payloads of any mass (Well, not ANY mass. Lag stomps on that dream pretty hard). As a result, the launch system is based around a single booster design, the Firefly Booster.

--- Firefly Booster ---

Specs:

Parts: 22

Cost (Dry): 43,349

Cost of Fuel: 1973

Cost (Total): 45,322 Funds

Mass: 36.2 tons

Each one of these boosters consists of 3 rapier engines, and 4 whiplash Turbo Jets and can support 12.5 tons of payload. Compared to a spaceplane, which could get away with 1-2 rapiers, this is horribly expensive. However, it makes up for it with its payload fraction, almost 25%, and its speed. When fully laden with payload, it can go from the launch pad, to circularization burn in under 10 minutes.

In addition, unlike a traditional space plane, the Firefly booster is easily scalable. Payload too heavy? Just add more!

If you don’t care for piloting, the FLS has you covered. All lifters in the system are Mechjeb compatible and all follow the same flight profile. In fact, for payloads approaching the max capacity of a lifter, Mechjeb is strongly encouraged since it can fly an FLS lifter fairly efficiently. (IMPORTANT NOTE: when using Mechjeb, you still have to switch the rapiers to rocket power manually when the whiplash engines flame-out)

Here are the settings for optimal performance.

· Limit acceleration to: 30 m/s (Very important for preventing explosions)

· Limit AoA to: 10

· Ascent path, Turn shape: 22%

Leave everything else at default.

If you prefer to pilot it yourself, the process is still fairly simple. This Imgur album will explain:

Controls for every FLS lifter:

ACTION GROUP 1: Toggle Rapiers

ACTION GROUP 2: Toggle Rapier Mode

ACTION GROUP 3: Toggle solar panels

Now, onto the lifters!

--- FLS Ixion-12 ---

Description: The smallest of the FLS booster line-up, the Ixion-12 is capable of lifting up to 12 tons into a 75x75 kilometer orbit. Not water safe (as in, it falls over and “disassembles”).

Specs:

Parts: 38

Cost (Dry): 59,939 Funds

Cost of Fuel: 1,965 Funds

Cost (Total): 61,904 Funds

Mass: 37.3 Tons

Payload fraction: 24.3%

--- FLS Varuna-25 ---

Description: The second smallest FLS Booster, the Varuna-25 is capable of hauling twice as much payload to a 75x75 kilometer orbit as the Ixion-12. It also isn’t water safe.

Parts: 71

Cost (Dry): 111,708 Funds

Cost of Fuel: 4,553 Funds

Cost (Total): 116,261 Funds

Mass: 79.9 Tons

Payload fraction: 23.8%

--- FLS Orcus-37 ---

Description: The workhorse of the FLS series, the Orcus-37 is the first FLS lifter capable of carrying a Jumbo-64 fuel tank into orbit. It is also the smallest lifter that is water safe.

Specs:

Parts: 100

Cost (Dry): 156,425 Funds

Cost of Fuel: 5,767 Funds

Cost (Total): 162,192 Funds

Mass: 115.3 Tons

Payload fraction: 24.3%

--- FLS Sedna-50 ---

Description: One of the largest of the series, the Sedna-50 is capable of lifting 50 tons into orbit. It also water safe.

Specs:

Parts: 127

Cost (Dry): 201,958 Funds

Cost of Fuel: 8,452 Funds

Cost (Total): 210,410 Funds

Mass: 151.6 Tons

Payload fraction: 24.8%

--- FLS Quaoar-75 ---

Description: The king of the FLS lifters (for now…), the Quaoar is capable of lifting an impressive 75 tons into orbit. Be warned though, at 175 parts, lag becomes quite noticeable.

Specs:

Parts: 175

Cost (Dry): 287,295 Funds

Cost of Fuel: 13,011 Funds

Cost (Total): 300,306 Funds

Mass: 233.8 Tons

Payload fraction: 24.3%

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Download links:

Firefly Booster: https://www.dropbox.com/s/7ldq6pqd9t7nbqn/Firefly%20Booster.craft?dl=0

FLS Ixion-12:

https://www.dropbox.com/s/fuu9qyjzkdfmpl5/FLS%20Ixion-12.craft?dl=0