Why does my SSTO lose control on take off

[Jarin]

3 minutes ago, Wanderfound said:

A shock cone is a good enough heatshield to hold 1,650m/s for a full circumnavigation of Kerbin if you do it high enough.

Mine tended to melt when adding another 100 m/s on top of that. Wouldn't last the full trip.Granted, I was also using Mk1 parts so I had to be better about dispersing internal heat.

[AeroGav]

I wouldn't go as far as using the 1.25m fairing unless i was trying to aerocapture in Jool or re-enter on Eve.   Mk2 inline with adapter and then either an intake (like Jarin in the top pic)  or NCS nose cone (as i tend to use, in my rework of the OP's ship) is sufficient.    

1500-1600 air breathing does not cause a heat bar, nor does the slow climb to orbit of a liquid fuel only nerv powered spaceplane.  Re-entry does not either, if you fly in with a little bit of nose up angle (5 to 10 degrees).  Come in prograde, a heat bar appears for about 30 seconds.

Yes you can get the pointy cockpit to orbit sacrificing delta V with a steeper climb, lower airbreathing top speed or by just letting it glow red hot and hoping for the best, but to me the benefits don't outweigh the risk.     Especially if you're sharing the craft on KerbalX or whatever, someone's going to blow it up then complain.     For the record, pointy cockpit

• looks fantastic
• 390kg lighter than the combo of inline + short adapter + nose cone system + small nose cone, even when the adapters are drained of their fuel (400 units in the mk2 adapter and 80 in the ncs adapter)
• pointy design has the dry mass further forward and the fuel mass nearer the CoM, which is more useful for offsetting engine weight and keeping CoM constant as fuel burns off.

Finally, with a pointy cockpit remember it's going to be the first thing to contact the ground in any prang.   Inline cockpits give Kerbals better chance to survive a bad landing.

[Joseph Kerman]

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