Help newbie on space plane landing

[Syczek]

For the starters i use FAR and many aeroplane parts(my latest creation is hybrid of B9 aerospace,airplane plus engine and stock swept wings,and aero breaks).Everything goes fine till i decelerate to 200 m/s my plane starts to fly down in sharp curve and violent hit up into ground. What i am doing wrong??

[Vanamonde]

Pics of the plane would help diagnose the problem, but I suspect the craft either doesn't have enough lift for its weight and is stalling, or doesn't have enough control authority to keep the nose up. 

[DeadJohn]

4 hours ago, Syczek said:

.Everything goes fine till i decelerate to 200 m/s

There are many possibilities and we need more info. Pictures of the plane will help. A craft file, too, but I think that's of limited us because someone will need all the same mods as you to test.

What's your altitude when you reach 200 m/s (if high, you might be slowing down too much and stalling in thin air)? Does the craft fly well slower on takeoff (if yes, your center of mass might be shifting after burning fuel)? What's your angle of attack on descent: sharply nose up? Are you going into a flat spin, tail slide, or just dropping like a stone after 200 m/s?

One thing you can try is to lower your nose a bit near 200 m/s, maintain velocity, then start nosing up again near runway to bleed off speed. If your plane still stalls at 200 m/s at sea level, you need to add wing area, or shift parts around to keep center of mass ahead of center of lift.

What's your takeoff speed? If you can't takeoff from the runway slower than 200 m/s you should probably add wings or adjust your center of balance and lift. Takeoff, cut your engines, and see how your craft glides.

As a last resort, if it's a wing area issue and you don't want more wings for whatever reason, come in very fast and trigger airbrakes, thrust reversers, chutes just before touchdown.

[Syczek]

https://imgur.com/a/NESX3XS

Mine Space plane. Builded from mods B9 Aerospace(i use all of them aside procedural ones),Mk3 Expansion (Engine) and rest is Squad parts(aka stock one)

https://www104.zippyshare.com/v/VwUWZOia/file.html Craft file.

Problems with landing as i said starts when i decelerate to lower than 200 m/s, Plane starts drop like stone when i lower trust and use brakes. Otherwise take off is smooth it requires 160 m/s to gain lift

Edited February 19, 2020 by Syczek

[Vanamonde]

Your center of mass is quite a distance ahead of the center of lift. I suspect that when you slow down, the control surfaces can no longer overcome the weight of the forward portion of the craft. Try shifting some of the wings farther forward. If you move the foremost wings especially, they will have more leverage.