Kerbal Galatic LKO tourbus challenge

[swjr-swis]

7 hours ago, Kergarin said:

Yes, but I had corrected this an hour before you quoted it. How did this work?

I honestly don't know. This forum keeps playing tricks on me - inserting replies before others that were already there when I replied, completely 'forgetting' I posted a message forcing me to repost to make it show up... nothing really surprises me anymore. So why not time warping too.

[Kergarin]

I don't want to spam this thread to much with CoM and CoL, but for everyone who is interested, here I have tested how big the difference can be on two extreme cases:

Spoiler

Full Album comparison at varoius speeds:
https://imgur.com/a/STeW349

 

Good CoL CoM at 100m/s:
Level flight with minimum pitch, small AoA, all surfaces provide lift.

 

Bad CoL CoM at the same speed:
we try to pitch up full, but the nose goes more and more down and the plane falls. The control surfaces provide drag and downforce instead of lift.

 

While the good CoL Version can keep level flight even down to 60m/s:

 

The bad CoL Version needs 240m/s to keep level flight, at full pitch up. And even then the control surfaces provide downforce instead of lift.
Thats 4 times the speed which the good CoL version needs for level flight using the same wings.

 

 

The version I have used in this challenge is a little behind the maximum forward Col to have a more stable reentry. And also to compensate a little CoM shift between wet and dry which was not avoidable in this design.

 

Edited November 27, 2018 by Kergarin

[TheFlyingKerman]

19 hours ago, Kergarin said:

That's why I would not try to land it on wheels.

But if you look at the picture where I approach the runway, you see in the navball that it flies surprisingly well.

Over and undershooting ist corrected by what you said: pull up hard and bleed off speed or fly straight like a bullet. Using the mk1 pod instead of the cockpit makes it verry heat resistant. (and lighter)

I also adjust the control surface authority for every phase of flight, to have more or less aoa.

Edit:

Also wings become much more efficient when the com col is correct. Com too far in front forces the control surfaces to generate drag instead of lift, or even downforce depending on wether they are in front or behind com.

I went to test this with my own SSTO rocket and conclude your landing method is feasible.

[Kergarin]

14 hours ago, TheFlyingKerman said:

I went to test this with my own SSTO rocket and conclude your landing method is feasible.

Thanks!  The forward Col in my comparison in an extreme sample. Your looks like extreme forward too. For the challenge my Col was a just little more backwards, so you it's a good balance between stability and agility.