KerbalX

Album contains 15 pictures.

ES-15 ICARUS (European Spacecraft model 15, Intra-Corona Activities Research - Understanding Sun) is a ion-powered probe with sophisticated thermal protection design. Its mission is to perform dangerously close solar fly-by and gather precious data from space near the Sun and its outer corona.

Key Features

• Stylish heat shield with active cooling system ensures safe operation at 180,000km solar PE.
• 7km/s dV from two ion engines, practical when performing bi-elliptical transfer with a very high AP (near Dres orbit).
• Ion engines can be safely and effectively used at solar PE for orbit maneuvering, such as lowering AP.
• Check Action Groups tab for key bindings.

Design Notes

• The concept is based on the NASA Parker Solar Probe (PSP) launched in 2018. On Sept 1. 2019, it completed its third close approach of the Sun.
• Icarus seems to be a common name for stuff related to the Sun, but I’m pretty proud of my reverse-abbreviation for this one.
• I use fairing with 2600k heat tolerance instead of dedicated heat shields with 3300k heat tolerance because it looks cool (main reason) and can be DIRECTLY cooled by radial-mounted radiators, which the heat shields can’t. Heat shields explode even earlier than the fairing in my tests, they seem not suitable for this particular design with many passive heat sinks and only one active one.
• The radial-mounted radiators won’t work at peak efficiency, because they only respond to the inner temperature of the fairing, which remains merely 600k while its surface has long been glowing at >2500k and is about to explode. I’m trying to understand the game mechanism behind heat management, and this project provided some really fun insights.
• There is actually no in-game scientific value getting too close to the Sun - anywhere under 1,000,000km would be equally considered space low over the Sun, unless you actually dive into its extremely hot atmosphere which seems impossible without cheating. To fly as low as possible and survive is merely an exciting thing and a personal challenge.

Mission Instructions

In spite of the maybe-exciting solar fly-by that may make you proud, it’s totally possible to find such a mission frustrating and/or boring.

Some unusual spaceflight techniques would be required. In the most important phases, it needs frequent manual intervention with limited or no time-wrap possibility. Total mission time would be more than 2 years in-game. Consider these before conducting the mission.

Launch

• Liftoff, conduct gravity turn and reach 45deg pitch @ 10km, lock prograde, jettison burnt-out SRBs.
• Push AP to 75km, shut down engine, coast till it escapes atmosphere, stage to jettison fairings, press AG4 to extend solar panels and antennas.
• Circularize. After first stage burn-out, it would require a very short kick with the upper stage.
• Now there should be ~4200m/s dV from the upper stage chemical rocket.
• Alternatively, transport the spacecraft+upper stage with a fully reusable SSTO spaceplane like shown in one of the screenshots.

Bi-elliptical Transfer

• Explanation on KSPwiki: HERE
• Escape from 75x75km LKO and push AP to near Dres orbit. This requires ~1470m/s dV if traveling in the same direction with Kerbin when escaping, gravity slingshot not in consideration.
• 1 year and 100 days later
• Near AP: use all remaining rocket fuel to de-orbit (sun-dive). This should lower solar PE to ~1,000,000km, exactly the boarder value between being high and low over the Sun.
• Decouple upper stage, hit AG2 to switch to horizontal control point.
• Use ion engines to further de-orbit and push PE into space low over the Sun. It’s tested for a safe fly-by with a PE of 180,000km, be extra careful under 200,000km. If you only want the low orbit science, >600,000km PE would be totally safe.
• It requires 2-3 charges for the ion engines to achieve lowest safe orbit altitude, however recharge takes merely seconds under maximum time wrap. Timing is not important: given how high the AP is, the spacecraft stays near AP for a pretty long time.
• Time-wrap to Moho orbit, prepare for the fly-by.

Solar Fly-by

• Hit AG1 to switch to vertical control point, lock radial-out (surface) to keep heat shield pointing at the sun, protecting the spacecraft.
• Extend top radiator.
• Use max. 100x time-wrap, otherwise the heat accumulation will go out of control and lead to the spacecraft exploding. Therefore, the fly-by would require a while to complete.
• Once the spacecraft main body begins to overheat, quit time-wrap, let it align itself to radial-out and enter time-wrap again. Repeat.
• Be extra careful under 200,000km. Use less time-wrap and quicksave a lot.
• Before quickloading, it’s recommended to use Alt+F12 menu to briefly enable ignore max temperature cheat, otherwise the spacecraft would likely explode upon loading. This is caused by sudden exposure to extreme heat source with no time for the radiators to react. Disable the cheat when it gets stable.
• Near PE, you can choose to fire ion engines to lower AP value. Rotate the spacecraft to let the engines face orbital retrograde while still having the spacecraft lock surface radial-out. They now work continuously with ridiculous power input so close to the Sun.

Wish you enjoy the sunshine!

Description

A stock rocket called ES-15 ICARUS Mission. Built with 82 of the finest parts, its root part is trussAdapter.

Built in the VAB in KSP version 1.7.3.

Details

• Type: VAB
• Class: probe
• Part Count: 82
• Pure Stock