Orbit Insertion? – Hux I-c1

Hux I-c on launch padEven before the Hux I-b probe had crashed into the ocean the scientists back at the VAB were modifying the I-b rocket for the first orbit insertion attempt. A Low Kerbin Orbit of 71km is planned.

The Hux I-c is essentially the I-b model but with an RT-10 solid fuel engine attached as the first stage below the LV-T45. Some other minor adjustments were made, with a second RCS fuel tank added beneath the the A.S.A.S. module of the now second stage, and a second set of 4 RCS thrusters at the bottom of the FL-T800 fuel tank. The winglets were also moved down so that they attached to the solid fuel engine. These additions brought the mass up to 15.12 tons and the TWR for initial launch down to 1.69.

A TWR of at least 1.7 recommended on the KSP wiki, and at the time of initial construction I didn’t have a way of getting the TWR without calculating manually. I have installed the Mechjeb mod now and it provides a whole lot of different stats about your rocket, including mass and TWR. There is also an autopilot function of it if you wish to use it, however I don’t wait to utilise that at this time.

First stage separation

First stage separation

Second stage separation

Second stage separation

 

 

 

 

 

 

 

 

 

 

Third stage separation

Third stage separation

The Hux I-c mission unfortunately ended in failure however a few lessons were learnt in the process. The fuel in the third stage was spent before reaching the apoapsis (71,637m) so an attempt to enter orbit from that point was no longer possible, however the Oscar-B tank attached to the probe did contain a small amount of fuel, and although there was not enough delta-v to make orbit it might be enough to at least lengthen the flight a bit. Shortly after firing the LV-1 engine, the KSC with it’s omnidirectional antenna was over the horizon and thus out of line-of-sight with the antenna on the probe. All remote control was lost.

Atmospheric entry

Atmospheric entry of probe

Tumbling out of control the probe re-entered the atmosphere and splashed down 11m29s after launch between a pair of islands 751.8km from the pad. A top speed of 2,059m/s was attained during the mission.

Before my goals get too ambitious I will have to eventually set up a network of relay satellites so that any unmanned craft I launch into Kerbin’s orbit will remain under remote control for their entire orbital period. Obviously manned vehicles don’t suffer these loss of control problems so once a launch vehicle is built capable of getting a reasonable sized payload at least to orbit altitude an attempt will be made to set up a small network of manned “command stations” in LKO.

I envisage a rather basic design for these, most probably just the command pod with some antennas and a small fuel tank and engine to conduct a de-orbit burn once the unmanned satellites are ready to be sent up.

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