Trouble landing small planes: boom!

[DarkGravity]

I've just returned after a year away. I started over in career, and I'm having trouble landing planes without sploding. I've got the LV 01s on the rear and a LV 05 in front. I'm not trying to land on the runway, just on the smooth ground surrounding campus. I succeed about 1 in 20 landings currently. I slow lateral speed to about 60 m/s and try to  get my vertical speed to under -10 (-5 if I'm really doing well). Seems pretty unforgiving. I remember landing planes for missions all around Kerbin a year ago where the land is not as smooth as near campus. Now I can't hardly land on the smooth ground. Any help will be appreciated!

[Evanitis]

Without seeing a screenshot of the plane, I'd probably blame the angle of descent. 60m/s horizontal should be slow enough - I did landings without a scratch by touching down at 80 m/s. (That's with Kerbal Krash Systems, so 'without a scratch' isn't just a figure of speech). That 5-10 m/s vertical speed sounds a bit too much though.

What I'd try is to level out the flight really close to the ground (like 30-60m), so you have a zero~ish vertical speed. Horizontal velocity doesn't really matter at this point, as if you pitch up carefully, you'll bleed the rest of the speed without losing altitude too fast.

Though a bumpy surface means you can't always keep an ideal distance and/or angle from the ground... That could make landings really tricky. I admit, I'm a lot better at picking my landing spot than touching down at a bad one... thus I kinda' almost always aim KSC or an ocean. Those are the flattest and softest spots to go for, the latter also saves the cost and weight of landing gears too.

Though by enough patience and f9 overuse, I'm convinced that anything can land virtually anywhere.

[DarkGravity]

Yeah. Tried another 50 landings. As gentle as I can. Not really any learning curve any more. The plane just sucks. I watched Scott Manley's vids and it is stable and all, but just no smooth control.  Have to wait till I can unlock better parts I guess. The retractable ones have twice the impact tolerance. Still much more unforgiving than what I remember from a year ago.

[bewing]

The LY01 and LY05 used to be indestructible. Physics has been added and now they are fragile. You cannot treat them like you used to, period. Don't carry more than 200 units of fuel, in a plane massing 5 tonnes, max.

The main point is that you need to learn to land like a feather. The grass at KSC is at an altitude of 66m. Scrub off your speed by porpoising before you get there. Get to a 75m altitude, in level flight. Cut the engines and just let the speed bleed off little by little by itself until your plane touches down. It should be below 55 m/s. (Then hit the brakes to prevent skidding.) Do not force your plane down onto the ground.

If you don't have smooth control, then adding length to the plane can help a lot. Reducing the "authority" of your pitch controls can help. Reducing the size of your pitch control surfaces can help.

Edited June 13, 2016 by bewing

[Van Disaster]

Double up on rear gear, use a braking parachute rather than wheel brakes until they sort wheels out. I'm also on the "too much vertical speed" bandwagon here, if I can't keep it below -1.5m/s I abort & go around.

Don't forget 10m/s is 36km/h... running into a wall at that speed is going to cause damage.

[bewing]

You did say "any help" -- so you might just want to try practicing on this plane: http://www.virtualrealitytoursllc.com/pix/basic_jet.craft

That's as easy to take off, fly, and land as a tier 4 plane can be, I think.

 

[ibanix]

Landing gear got a lot more fragile with 1.1. My gear sometimes explodes at 80m/s on *take off*. 

You want less than 5m/s vertical and less than 50m/s horizontal speed on landing, to have a good shot not to explode landing gear. 

[Sir Mildred Pierce]

I'm kind of in the same boat, I mainly like to design rockets and do space stuff, but I decided to try out doing planes after not being in to it after a long while.  As far as I can tell, looking over what other people have said, is that after 1.1 came out the physics for planes seems a lot different.  I can barely control them now, even stock planes pretty squirrely.  Taking off has become a severe headache.  The landing gear are really touchy now and you have to have them perfectly aligned now, it seems.  Even when I get the landing gear aligned I spin out on the runway way too much.  If you can get your plane to take off and is stable in flight you are ahead of me.  Designing and flying planes just isn't enjoyable for me anymore and I think I'm going to stick to rockets.

[Snark]

And just to be clear about landing-gear fragility:  size matters.  Bigger gear can take a lot more punishment than smaller gear.

It really matters how many tons of aircraft are coming down on each gear.  And landing generally puts more stress on the gear than just sitting or taxiing on the runway, so a plane that seems fine on takeoff may actually be dangerously overloaded.

The smallest-size landing gear can only handle very light loads.  If your landing gear keep going poof on landing, try replacing them with one-size-bigger gear.  I did that, and suddenly all my landing problems went away-- can land a plane just fine, even on the bumpy green grassland terrain west of KSC, no problem.  And that's just flying mouse-and-keyboard, and I am by no means an airplane jock.

To take an extreme example:  just for grins, I tried mounting four of the biggest-size gear to a tiny test craft that was just a couple of tons, launched it vertically with a rocket engine, and brought it straight down into the ground at 50 m/s.  Result:  Bounced lightly once and then settled down unscathed.  Totally unharmed.  Reason?  Ludicrously light mass loading compared to the size and strength of the gear.

So:  It's not "how gently you land the plane" that matters-- it's how gently you land the plane times the plane's mass, and then divided by the size/strength of the landing gear.  Lighter plane and/or bigger landing gear, and you can do some pretty rough landings with no problem.

[Kerbart]

42 minutes ago, Snark said:

And just to be clear about landing-gear fragility:  size matters.  Bigger gear can take a lot more punishment than smaller gear.

It really matters how many tons of aircraft are coming down on each gear.  And landing generally puts more stress on the gear than just sitting or taxiing on the runway, so a plane that seems fine on takeoff may actually be dangerously overloaded.

In addition, IRL large airplanes can't land with a full load of fuel. So if you're taking off with a boatload of fuel for a quick test flight you're going to have to find a way to get rid of all that fuel before you land, lightening the load on the gear significantly.