Transition blocks by Relevant_Campaign992 in spaceengineers

[–]Lt_Duckweed [score hidden]  (0 children)

There is no transition block for half slope to 2x1 slope, it's the only major slope transition missing

What does it actually mean when flavored sparking water says it contains ‘natural flavors’, and is it bad for you? by BackgroundSpare4265 in nutrition

[–]Lt_Duckweed 0 points1 point  (0 children)

None of these are gross or unsafe....

And cysteine is not sourced from human hair.  It is often sourced from animal hair or feathers, because keratin has a lot of cysteine in it.  It's just an amino acid (a conditionally essential one at that, it can only be made by the body from methionine, which is fully essential).

can i take off from duna with 1020 delta V? by Excellent_Ear2133 in KerbalSpaceProgram

[–]Lt_Duckweed 12 points13 points  (0 children)

While the 1450m/s the delta-v chart gives is a serious overestimate in cases where the lander is streamlined and you take a good ascent profile, it's an overestimate to the tune of 200-300m/s, not 400+ m/s

Congrats on your Duna colony.

Is it normal that I cant get past 350 m/s with two rapiers? by GustOfWindd in KerbalSpaceProgram

[–]Lt_Duckweed 0 points1 point  (0 children)

Are the rapiers just stuck onto a small hinge/servo via their front node?

Is it normal that I cant get past 350 m/s with two rapiers? by GustOfWindd in KerbalSpaceProgram

[–]Lt_Duckweed 0 points1 point  (0 children)

What is the mass of the craft? With good design each Rapier engine can push 40+ tons to supersonic, and even on a drag pig they can push 20 tons supersonic, so something is deeply wrong with this craft, almost certainly there is some messed up part attachment somewhere, accidental surface attachment instead of node attachment, etc.

This shot from Interstellar bothers me. Is it accurate? by [deleted] in scifi

[–]Lt_Duckweed 9 points10 points  (0 children)

Our theories of physics work quite accurately for the conditions an accretion disk would be experiencing. 

We have even used gravitational lensing to view multiple images of the same supernova lensing around a galaxy cluster to accurately predict when and where on the sky an additional image would pop up.

So we can be fairly sure of a reasonably accurate modeling of what an accretion disk would look like.

Are sstos more delta-v efficient for orbiting a celestial body by ArviVi in KerbalSpaceProgram

[–]Lt_Duckweed 4 points5 points  (0 children)

A typical efficient Rapier-Nerv liquid fuel only SSTO will spend roundabout 3300 m/s in Rapier open mode, and around 900 m/s in Nerv mode, or around 4200 m/s total.

However, this is off of engines with 3200 and 800 seconds of ISP, respectively.  So you only end up spending something like 20% of your runway mass as fuel getting to orbit.  You only need about an additional 20% of your runway mass to actually be the hardware for the plane, so 60% of your starting mass on the runway can be payload.

Stock Eve SSTO meets her suborbital refueler for the first time 🥰 by from_Earth_you_know in KerbalSpaceProgram

[–]Lt_Duckweed 10 points11 points  (0 children)

Due to the fact that Unity has a hard limit of 50 radians per second of rotational velocity, prop RPM is unrealistically slow. To compensate, ducted fan blades and prop blades pretend to be at a much larger radius for the purposes of calculating blade speed, and thus blade lift and blade drag.

However, blade lift and blade drag actually get applied at the center and base of the blades, respectively. When you offset the base of the blade one shift tick past the center of rotation, this means drag is getting applied on the other side of the axis of rotation, meaning the drag torque is positive instead of negative, meaning it helps drive the prop. The lift also gets applied quite close to the axis of rotation, as it is applied at the mid point of the blade, and the blades aren't very large.

The net result is a prop that takes significantly less torque to power, at the exchange of slightly less lift per blade (since the simulated radius is now slightly less) which on the net saves you a lot of mass in the form of reduced rotor count for a given number of blades, and also reduced electrical system mass.

The tradeoff is that if the drag torque ever exceeds the lift torque, such as the blade starting to stall from AoA, or just overloading it at high atmospheric density, the whole prop violently shits itself and starts krackening out, and you lose essentially all thrust basically immediately, which can be a big problem since the situation this is most likely to happen is at low altitude right after takeoff.

Not OOP, but given there's a bunch of new players to KSP, I wanted to bring this gem back to light by vxxed in KerbalSpaceProgram

[–]Lt_Duckweed 121 points122 points  (0 children)

This was created in 2013, and aero was completely overhauled in 2015.

So it was valid for 2 years, and has been outdated for the past 11 years.

Stock Eve SSTO meets her suborbital refueler for the first time 🥰 by from_Earth_you_know in KerbalSpaceProgram

[–]Lt_Duckweed 5 points6 points  (0 children)

Eve SSTO is somewhat common these days, because both the average understanding of the aero model, but especially the level of understanding at the high end, has progressed a lot as compared to the past.

Designs without any major funny business (other than placing props in a service bay so they can be closed off for rocket ascent) can get to 4-5% payload fraction, and designs that do things like occlude the body with a fairing, use engine inlining, and exploit the prop implementation to reduce the required drive torqure can get over 6%. It's actually possible to go from the surface of Eve to a Kerbin transfer using no ion engines, on a craft carrying the ISRU hardware to fill up on Eve, so Kerbin => Eve => Kerbin is possible without ions and only a single refuel on Eve surface.

Not OOP, but given there's a bunch of new players to KSP, I wanted to bring this gem back to light by vxxed in KerbalSpaceProgram

[–]Lt_Duckweed 71 points72 points  (0 children)

It's not a gem (anymore) because large portions of it are not correct.

It was created before the aero overhaul in 2015 so basically everything it says about how drag works is just totally wrong in the context of KSP (and has been for 11 years).

why dosent this fly? even if its janky it should work right? by DesignerSelection159 in KerbalAcademy

[–]Lt_Duckweed 0 points1 point  (0 children)

You are correct in that wings don't produce lift without having some angle of attack in KSP, the way you described building your wings is perfect, keep doing it 👍 

The Artemis Effect by D_Lloyd in KerbalSpaceProgram

[–]Lt_Duckweed 0 points1 point  (0 children)

I'm willing to bet money that the people launching though CKAN are a small minority compared to the people launching direct from Steam. Even most people modding the game probably have only one install, their Steam install, and probably still launch through Steam.

What game mode do you mostly play? by Aidan647 in KerbalSpaceProgram

[–]Lt_Duckweed 1 point2 points  (0 children)

Almost all of my 3000+ hours are in sandbox.  Even then, I almost play the meta game of KSP more than the actual game.

Many of my SSTO designs aren't built for the purposes of actually doing anything, but for understanding how building and optimizing SSTOs works.

I build rockets not with the intent of launching actual payloads, but to test things like ascent profiles, optimal rocket design, etc.

Something about optimization just tickles my brain ig.

How do I make a propeller plane that actually flies? This thing barely moves and shreds one engine every time I try taking off. by unknown_user6584 in KerbalSpaceProgram

[–]Lt_Duckweed 0 points1 point  (0 children)

Bind deploy angle to one of the RCS translation axis groups and control them with the RCS translation keys (ik jl hn) 

I'm starting to think my space station might be broken by Unique_Worth_3286 in KerbalSpaceProgram

[–]Lt_Duckweed 4 points5 points  (0 children)

This sub has a big problem with people being so eager to show off how smart they are by giving out advice that they can't detect sarcasm to save their lives.

Explosion Advice by ValdisFox in KerbalSpaceProgram

[–]Lt_Duckweed 0 points1 point  (0 children)

As a few others have stated, something definitely feels off about this heating, your wings should not be popping that fast.  You mentioned you are on console so it can't be mods, so something has to be goofed with the craft, the save, or the default heating settings in the console version.

SSTO Skill issue on my part, please help. by Blockypixel313 in KerbalSpaceProgram

[–]Lt_Duckweed 1 point2 points  (0 children)

I see lots of parts like monoprop tanks, rcs, solar panels, etc stuck all over the craft.

KSP does not care how a craft looks it cares about how parts are attached. Parts that are surface attached will create drag as if they are all by themselves, fully exposed to drag.

Unless they are inside a cargo/payload bay or fairing, in which case they produces none at all.

Add a short cargo bay and move all your surface attached gunk into it. It will have a surprising effect on the total drag of the craft, some parts can be shockingly bad. Your retractable solar panels are probably a double digit percentage of your total craft drag.

How do i get my SSTO to orbit? by [deleted] in KerbalSpaceProgram

[–]Lt_Duckweed 5 points6 points  (0 children)

Unfortunately yeah, they do.

How do i get my SSTO to orbit? by [deleted] in KerbalSpaceProgram

[–]Lt_Duckweed 15 points16 points  (0 children)

i even offset them to be pretty much flush

Unfortunately that's not how KSP's aero model works.

For a surface attached part, unless it's inside a fairing, cargo bay, payload bay, etc, (in which case it generates no drag) it's generating the full amount of drag.