Landing a plane without air brakes possible?

[f.meussen]

I am doing career mode of Kerbal, just got the parts for a very basic plane ( so no airbrakes available yet )
No matter what i try the plane ALWAYS has too many speed to land properly.
Normal plane ( real life ) you extend flaps, drop gear ( also not possible yet with basic parts ) lower the airspeed , pitch the nose a little bit up and the plane drops out of the sky in a controlled matter.
This technique is impossible in Kerbal, first does this game know the principle of flaps? ( high lift /drag on low speeds )
Is it possible to make a controlled landing with just the basic plane parts?
Is it even possible to stall a plane? ( rocket yes but plane always seems to have enough speed )
Anything else i need to know?

[Yuki]

Originally posted by XLjedi:

^^^ Ignore him... [everyone]

But he's right. (OMG did i say that?)
In RL you never use D-chutes in mid air- on airplanes.
Because of the angle of attack (attached to the back usually) it would make your nose point down, the one thing you never want. And the same happens in KSP.
However similar to RL there is another use for them mid flight: During vertical landing.
Like they did for the Mars rovers, and especially on early Duna missions i like to have a D-chute to stabelize my craft. Nose mounted it makes sure my nose will be pointing up while it still doesnt alter my flight path too much so i can adjust with RCS to bring the new module really close to my base.

As for KSP airplanes: Chutes and D-Chutes seem to have a different curve in regards to effectivity at x-speed. D-chutes seemingly behaving linear while chutes actually work better at lower speeds. That can potentially make it possible to use D-Chutes before touch down, however that also translates to: they are too weak to have much of an impact anyways.

BUT- we where talking about starting tech airplanes here. Honestly, the only thing i use chutes with (yes chutes, not D-Chutes, for the reason Roofy mentioned) is my 600T+ Apophis class SSTO. Because it just exceeds normal KSP tonnage by this much, the brakes on the wheels simply give up. And being a highly drag-optimized hypersonic design its landing speed well exceeds 100 m/s... The 400T Osiris class can still land without pretty fine. That is starting weight though, if the Osriris class lands without leaving its cargo in space it might be too much again.
But thats as far from starting tech as it gets.

[XLjedi]

Originally posted by Yuki:

Originally posted by XLjedi:

^^^ Ignore him... [everyone]

But he's right. (OMG did i say that?)
In RL you never use D-chutes in mid air- on airplanes.

...there are plenty of things we do in Kerbal-land that no one does IRL. However, if your goal is to mimic reality. A ridiculously over-sized recovery chute deployed from the back of an F-35A ain't gonna cut it either.

[RoofCat]

I suspect drogue chutes in KSP are more rocket oriented drogue chutes. A bit more like those used for Mars landings - deployed at much higher velocities than drogue chutes you would use on planes. KSP drogue chute ceiling is somewhere above 400m/s iirc - which is f. supersonic 1440km/h! Doesn't sound much like a plane landing :)

They are a bit more universal than real life Mars chutes, even more so considering KSP universe differences (planes chill flying at MACH 4 with Whiplashes) and landing at 600km/h, but still they aren't great at slow speeds.



Another interesting thing - while experimenting with airbrakes I got really weird impression those are close in performance to a drogue chute. I may be really wrong and far off here, as I did just some short tests a while back, but somehow airbrakes seemed much more efficient than I would have guessed just looking at their size compared to drogue chute size. Which made me prefer airbrakes over drogue chutes when light slowdown was needed on some craft.
Because they are actually slightly lighter, almost as good (seemingly?) and can be used again and again even shortly when needed or really high during reentry before the heat goes crazy.

I would be interested to hear opinion from others on airbrakes vs. drogue chutes. Even better if someone has done more accurate tests or research in KSP data files.

[XLjedi]

Originally posted by RoofCat:

I would be interested to hear opinion from others on airbrakes vs. drogue chutes. Even better if someone has done more accurate tests or research in KSP data files.

You should start a thread instead of hijacking this one. I would recommend the title "airbrakes vs. drogue chutes"

[RoofCat]

Originally posted by XLjedi:

Originally posted by RoofCat:

I would be interested to hear opinion from others on airbrakes vs. drogue chutes. Even better if someone has done more accurate tests or research in KSP data files.

You should start a thread instead of hijacking this one. I would recommend the title "airbrakes vs. drogue chutes"

dude, this topic is literally about landing with/out airbrakes. Chill, no one is attacking you. We are just talking game physics here.

[XLjedi]

@roofcat dude, go back and delete more of your one-off non-constructive comments as you continue to google topics after the fact. Don't worry, I won't actually quote the really stupid things you say. With the hope that you might delete them as you have on this thread.

If you start a new thread, I'll at least commit to reading thru your entire first post.

[RoofCat]

Originally posted by XLjedi:

@roofcat dude, go back and delete more of your one-off non-constructive comments as you continue to google topics after the fact. Don't worry, I won't actually quote the really stupid things you say. With the hope that you might delete them as you have on this thread.

If you start a new thread, I'll at least commit to reading thru your entire first post.

are you still trying to talk about me or ingame physics regarding topic - landing slowdown. I'm confused.

[Toastie Buns]

Originally posted by RoofCat:

I suspect drogue chutes in KSP are more rocket oriented drogue chutes.l

They were originally designed for duna and kerbin returns

[RoofCat]

btw I just did a small test with airbrake vs. drogue chute on a plane. Single Rapier MK2 with ~50m/s takeoff speed. Seemed the best way to compare drag performance.

Drogue chute limited velocity to ~90m/s at full thrust while single airbrake allowed ~270m/s. Two of them ~200m/s. So they aren't that close in performance as it felt to me a while ago during some descent (can't remember which body and what exactly was in need of a slowdown back then).
Not sure about different air density or some hidden velocity related performance curve at very high or very low speeds. Also you have to keep in mind how Rapier thrust grows gaining speed, but still it seems airbrakes are not nearly as potent as drogue chute. I have had decent results with them on Laythe SSTO and few other planes, but I suppose those weren't pushing slowdown limits that hard.

Just in case - regular chute installed on the same setup reduced top speed to 24m/s very quickly and that of course wasn't sustainable in flight even with Rapier working full thrust unlike the other too. Which again confirms great performance of regular chutes at low velocities needed for braking on runway.

[Yuki]

Airbrakes are often more effective at higher speeds and do work different to d-chutes in some regards. Of course that also depends on size. However they also seem to have a more linear effectivity curve like d-chutes as opposed to chutes.
Their effectivity just "climbs faster", i suspect to enable use during landing. (comparing my early d-chute vs late duna landers, i use gliders with airbrakes later on, the air brakes are way more effective in upper/mid atmosphere, slow the craft down way more)

Their force application however seems to be different:
Hypothesis: D-chutes apply their force in an angle at their point, RESULTING in a certain torque and slow down force.
Airbrakes and elevons apply their force as a direct slow down force and then a bit of torque independently. enabling them to have higehr slow effectivity without likewise high impact on flightpath.

A behavior seen in some physic engines, different declaration of certain items. Would even make sense to solve it that way given how you usually use those two items. And theybehave like this, for example:

Sometimes my SSTO flip around and enter re-entry backwards. Don ask why :P
Trying to flip them back now results in them just twitching a tiny bit, but can exceed 5G in slow down force. So i wait a moment and...the same SSTO may have a d-chute at its back. So about where the elevons sit as well. Activating the (single small less effective) d-chute will immediately pull the craft around with violent force, at way lower slow down G-forces (but for a moment massive rotational G).

And air brakers can be activated at even higher speeds!
Which is where i use them, or actually: those "self made" airbrakes shown above.
Airbrakes are a nice way to ensure a fast yet still kinda safe re-entry, also on pod designs.

I did not notice any differences between self made and stock air brakes (other than size and hence force). Both however seem to not just work on the drag model, but somehow apply a slow down force immediately, like all elevons do the moment they move. Stock-airbrakes now do only apply this force without much steering, while self mades need to be set up properly, else you will spin around like crazy.

Self make air brakes on space planes then again tent to be WAY more heat resistant.
They are perfect for slowing down in upper atmosphere all the way even into re-entry. If you play hard mode with black outs, they become a must to keep those tourists alive. Proper use required, air brakes at full extend at certain points during re entry can then again skyrocket your G forces to >15 in the blink of an eye...
Or i also tent to use an atmobrake on moon returns for a direct intercept of my LGO station. Hitting B a few times for fine tuning is certainly better than cutting chutes ;)
Plus they indeed still slow you down during landing, again a matter of size.
The version in the picture above is defy already very "noticeable" during landing.

[Toastie Buns]

Pretty sure old roofcat1 logic was that an airbrake is better than a drogue at duna. Kerbin has a variety of ways to slow down, even gear help

I still maintain willies make good airbrakes
https://streamable.com/9dr20
https://streamable.com/0s06r

[Aereto]

I've had some aircraft designs that used those frail landing gears, especially in career mode, without airbrakes.

While unsure if it will help, but turning off any reaction wheel torque helps getting the feel of how the craft steers by air alone. As what others suggested, maneuvering helps bleed the velocity off, but considering starter aircraft part choices, be very careful not to go too slow as to lose lift and let the wheels take the brunt of the vertical speed.

From past experience, I have some of my designs stalled or even go into flatspin.

[RoofCat]

Originally posted by Yuki:

Airbrakes are often more effective at higher speeds and do work different to d-chutes in some regards...

Their force application however seems to be different:
Hypothesis: D-chutes apply their force in an angle at their point, RESULTING in a certain torque and slow down force.
Airbrakes and elevons apply their force as a direct slow down force and then a bit of torque independently. enabling them to have higehr slow effectivity without likewise high impact on flightpath.
...

Yes, I may have got that impression at some Duna landing test. Probably at Duna or simulating it at 15km on Kerbin, not sure. I really don't use airbrakes that much and drogue chutes really rarely in finished craft. I solve initial braking with designs and gliding for the most part.

Regarding the other part - a few weeks back I did tests with chutes (regular ones) in different setups. You know there are weird results whether you use the nose chute or the radial one. Both 0.1t, in description radial one actually has larger area. But the nose chute performs better. Then I did tests with more radial chutes and suddenly they were as good.
So the "weird" part - multiple radial chutes have to push each other to sides (bend at an angle to form the wide multichute "umbrella") to have best slowdown. Place them wider apart on some long Kickback shell or at different heights to avoid interaction and they won't slow down as good.
It's easy to test with landing speeds at KSC.

I guess there is some physics reason for that. I'm just not as good with aerodynamics. Not even close. Or it is just a "feature" of Unity engine and to avoid superpowers in multichute setup, Squad may have reduced the single radial chute efficiency by default as they are mostly used in swarms unlike nose chutes.

I haven't tested multiple nose chutes pushing each other, but I would guess similar performance. Not sure, more like 60/40.

[Mightylink]

I land without air brakes most of the time, you just need to be going slower while landing. I only ever needed them for the space shuttle because you come in steep without engines and this thing I made because it takes the entire runway to slow down x.x
https://steamcommunity.com/sharedfiles/filedetails/?id=1117430369

[Gojak_v3]

I'd just put a parachute on planes. If it looked like the landing wasn't gonna go well I'd just cut engines and deploy it. You can generally make it down that way without crashing.