KerbalX

Description

The Kanneli XL is a mining/refueling capable SSTO airliner, capable taking 20 Kerbonauts to LKO with 6000 m/s of dV remaining.

The Kanneli (translation: Yellowfin) XL is a highly modified and enlargened version of the original craft. Adding an extra 900m/s in LKO as well as refueling capability, your boundaries are pretty much endless, apart from Eve/Tylo for obvious reasons.

Whilst still a relatively compact vessel, the mass has been increased by a whopping 85 tons. The MOAR boosters strategy is replaced with MOAR wings. Only one Rapier and two Nukes are added, and the extra wings are clipped so as to keep the dimensions down. A bit of not-so-obvious aerodynamic trickery is used with part attachment to help reduce drag. The one flip side to this is that the craft is a bit more fragile, thus some care is needed when maneuvering at high speeds in thick atmospheres.

12 RTGs and 3 fuel cells provide all the electrical power needed, removing the need for external batteries and solar panels. The ISRU and drill can fill up the craft relatively quickly when operated with an engineer onboard, and two drain valves are capable of rapidly defueling the craft. Whilst the VTOL engine has been removed, the craft can still land on it’s tail and the nose be lowered. The nose also contains a parachute to help make Duna landings easier.

Built in the SPH in KSP version 1.9.1

Launch Profile (video above)

It is recommended to keep precision controls on throughout the flight. Kerbal Engineer is highly recommended for the readouts it provides. One engine may temporarily flame out on the runway until you get some speed; the manufacturer insists this is a design feature, and definitely NOT caused by having only 2 intakes for 7 rapiers.

1. Space to activate Rapiers, if you have an asymmetric flameout, use the rudder to keep yourself centered.
2. Lift off at 105m/s, minding the tail. Tap F to maintain altitude below 100m and accelerate.
3. Maintain level flight until you reach 380m/s, then let the nose come up by itself.
4. At 6km, tap F until the nose is on the horizon, maintain this until 1350m/s, then let it come up again.
5. Your target is 1500+m/s by 20km, at just under 10 degrees pitch.
6. At 20km, press 3 to activate NERVS. When your speed starts decreasing, slowly tap F to maintain it.
7. When your Ap is above 28km, lower the nose to just above prograde.
8. At 28km, press 2 to shut intakes, when Rapiers flame out, press 1 to switch to ClosedCycle.
9. Pitch up to 20 degrees and maintain, switch velocity to Orbital readout.
10. When ORBITAL velocity reaches 2030m/s, set SAS to prograde. At 2050m/s, press 4 to shut off Rapiers.
11. When time to Ap reaches 15 seconds, nose up to 20-25 degrees as required to maintain your time to Ap.
12. As your time to Ap starts increasing, slowly start lowering the nose to 10 degrees, then maintain.
13. When Ap reaches 60km, hit prograde and hold. At 76km, shutdown the nukes.
14. It’ll take about 12 minutes to reach Ap, you may use x4 Physics warp with the nose held to prograde.
15. Once you are out of the atmosphere, make a small burn to set Ap to 75km, then circularize.

Re-entry from LKO (tested to 164-tons craft weight)

1. Aim somewhat past the old-island airfield, and target to deorbit with a 140-ish m/s burn.
2. Pitch attitudes of 10-15 degrees will increase your range, 25 degrees or higher will decrease it.
3. It is recommended to keep the nose under 40 degrees above the horizon.
4. There’s a secondary stability point at around 50 degrees, but there’s enough pitch authority to recover.
5. Pitching down too aggressively could put you in spiral, however they can be recovered from rather easily.
6. Keep maneuvers below 5g especially at higher weights until you’ve slowed down below 400m/s.
7. The CoM will move quite far forward, so give yourself enough space to pitch up for the landing flare.
8. Land at 90-120m/s (50-80m/s at 75-tons), lower the nose then use the brakes.

Refueling operations

1. Pressing 7 will activate the fuel cells, open the cargo doors, lower the drill and extend the radiators.
2. Start the surface harvester, activate LF-Ox on the ISRU FIRST, then activate LF-only.
3. When the craft is full, stop the ISRU, press 7 to pack everything up.
4. Remember to jettison any excess ore on the small holding tank above the ISRU.

Operational tips

• Generally, it’s recommended to fuel-up only as much as you need, but have plenty of Oxidizer reserves.
• The drain valves on the sides are set to rapidly drain the fuel, adjust the rate as you need.
• Due to the large mass, Rapiers will most likely be needed for most landings and takeoffs.
• The nosewheel steering is disabled by default, press 5 to toggle it.
• While a guide cannot be provided for every body, a general tip for landing is to use NERV’s first and add Rapiers later on.
• The opposite applies for departure, use Rapiers and NERVs if needed to take-off, then shut the Rapiers down.
• Use the parachute when safe on Duna, if no immediate deployment, right-click and lower the deployment pressure.
• The chute can be repacked by an engineer after landing, s/he can climb up the ladder to the top of the craft.
• I cannot stress the importance of quicksaving enough! Crashes are not covered under warranty without quicksaves.
• Ironically, a quickload when flying in the atmosphere will likely cause the wings to shear off, refer below for the fix.
• If flying in the atmosphere, use the cheat menu and tick unbreakable joints until the craft has loaded, then untick it afterwards.