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Sorry if this was answered before, but is FAR acceptable to use or is everybody using the stock aero physics?

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Ok. I've got a really chonky ssto called the "Maiden", but it needs an extended runway, as it is so heavy. Is it ok, if I take off on the fields around the KSC? Thanks!

Also, I'm going for the heavy rain division- 333 tons

Know what? Scew that. It can't even take off at 140 m/s with an extended runway

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17 hours ago, έķ νίĻĻάίή said:

Ok. I've got a really chonky ssto called the "Maiden", but it needs an extended runway, as it is so heavy. Is it ok, if I take off on the fields around the KSC?

I'm more concerned about the "SSTO" part, since Rule #7 states that you must stay below 35 km ASL at all times. You should be okay as long as you stay within the atmosphere. 

 

Also, just how long does it take for your plane to reach takeoff speed? Personally, I would suggest:

  1. Applying the brakes
  2. Starting engines at full throttle.
  3. Waiting a bit (I don't know how long for you) for the engines to warm up.
    1. Jet engines take a while to reach maximum thrust output.
  4. Releasing the brakes for a faster takeoff speed.

 

18 hours ago, έķ νίĻĻάίή said:

Also, I'm going for the heavy rain division- 333 tons

333 tons? My Poseidon SSTO weighs only 184. If you can take off, fly around Kerbin, and land in one piece in less than 80 minutes, then I say go for it.

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4 minutes ago, Raptor kerman said:

For the record, the Kerbin circumnavigation record by plane is ~37 minutes.

Tell @nelso that.

 

  • And this isn't even his best time.

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22 minutes ago, Mars-Bound Hokie said:

Tell @nelso that.

 

  • And this isn't even his best time.

Realised my mistake, asked the mods to remove the post. The post was based on the old kerbin (air breathing) circumnavigation challenge where the record was at around 37 minutes. Bear in mind, I saw this thread and didn't read the posts. 

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Okay, I'm mounting a serious attempt at this challenge. I have spent an incredible amount of time making 1600 m.s^-1 ULR aircraft. But I haven't done circumnavigations in a LONG TIME.

Question: what is the distance to travel the full circumference at the equator? 

 

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jwMQP8u.png

 

Which means that, in order to pass the challenge, you have to go around the planet in less than 80 minutes:

EbFYe5M.png

 

Now, that does not mean that you're fine if you cruise at 786 m/s. This average time also includes the time it takes to take off, get up to speed, and land.

  • And yes, your total entry time includes takeoff and landing (up to a complete stop)

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8 minutes ago, Mars-Bound Hokie said:

jwMQP8u.png

 

Which means that, in order to pass the challenge, you have to go around the planet in less than 80 minutes:

EbFYe5M.png

 

Now, that does not mean that you're fine if you cruise at 786 m/s. This average time also includes the time it takes to take off, get up to speed, and land.

  • And yes, your total entry time includes takeoff and landing (up to a complete stop)

cheers, just fleshed out basic operational requirements, and I'm looking at a a cruise speed of 2100 m.s^-1  among other things. While I have previous high-alt, high-speed experience, this is completely new for me. I'm wondering if I've bitten off more than I can chew.....

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8 minutes ago, Raptor kerman said:

Question: what is the distance to travel the full circumference at the equator? 

It depends from that runway you take. If you take off from 09 (bearing 090 - as AFAIK it's the intended bearing on the challenge rules) and keep going, at 1400ms (my previous entry), KSP says you travelled about 5.860 Km.

I understand that this is due Kerbin spinning under you once you reach some altitude: the more time you spend flying, more time Kerbin have to spin under you, "pushing" the destination a bit further.

My previous entry took ~50 Min, or ~3000 secs, to circumnavigate Kerbin. Well, If I travelled 5.860Km in 3000 secs, I had an average speed of 1,89333333 Km/Sec. What's impossible, because my top speed was 1,4 Km per sec! :D 

As in the previous post, Kerbin has ~3.770 kms on the Equator. Since the day on Kerbin is 6 hours, Kerbin "runs" 3.770 Km each 6 hours, or ~628.33 Km each hour, or ~174m/s.  Problem is.... At 174m/s, on 3.000 secs the distance covered is about 522 Kms, 25% of the difference between what KSP says I traveled and the circumference of Kerbin: 5860 - 3770 = 2090.

Furthermore, Forum says that the Kerbin's atmosphere rotates together the ground, so that 174m/s should not influence your travelling.

But so, why KSP says I travelled 5.860 Km? :P If someone has an explanation, I'm hearing! :)

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I'm not counting this as an entry ATM, but to show that FAR does not affect the heating of the plane's parts at high speeds. It just alters how the game looks at the plane as a whole, not as individual parts.

Anyhow, this is what I did. I did lose the nose antenna (does help with the aero in FAR) so it's disqualified as is.

vcO8RCh.png
JWgtn6x.png
wEjckpy.png

Not too shabby for a single Whiplash powered Jet plane. :)

Edited by GDJ

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15 hours ago, Mars-Bound Hokie said:

I'm more concerned about the "SSTO" part, since Rule #7 states that you must stay below 35 km ASL at all times. You should be okay as long as you stay within the atmosphere. 

The battle plan - Since the Maiden class SSTOs carry a lot of oxidiser, I’m just going to use the rapiers in closed cycle, meaning that I’ll have MOAR POWER under 35km where they usually lose power due to lack of air

Edited by έķ νίĻĻάίή

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AHH

STILL WON'T TAKE OFF

Screw that! Time for plan B. I'm (hopefully) goint to take off with rapiers in closed cycle

ok so takeoff speed is more then 160 m/s (sigh)

time for plan C

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Ok. Done! 

The flying dorito runs for the Heavy rain division.

 

Spoiler

Mission starts!

270.png

Going...

273.png

Night already?

282.png

Day.

286.png

Almost!

294.png

Landed!

298.png

In 63 minutes and 48 seconds.

 

 

 

 

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On 1/21/2020 at 1:28 AM, GDJ said:

I'm not counting this as an entry ATM, but to show that FAR does not affect the heating of the plane's parts at high speeds. It just alters how the game looks at the plane as a whole, not as individual parts.

I'm toying with FAR now and then, and I like the new challenges it imposes - as the CoL changing on supersonic speeds. I agree that it makes aircraft designs more realistic - some stunts just doesn't pays anymore (or even works at all) with FAR.

However... I think that FAR should be applied on specific Challenges just for it.

-- POST EDIT --

About the rule of the craft being capable of landing.... I ask that the rule doesn't imposes that the landing must be done on the same run. By the time I get my high score, I end up without fuel to the journey home!

Edited by Lisias
I dont have the slighest idea how I edited this here. This was meant for the other challenge!!! Jeez... =P

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On 1/20/2020 at 11:24 PM, Lisias said:

It depends from that runway you take. If you take off from 09 (bearing 090 - as AFAIK it's the intended bearing on the challenge rules) and keep going, at 1400ms (my previous entry), KSP says you travelled about 5.860 Km.

I understand that this is due Kerbin spinning under you once you reach some altitude: the more time you spend flying, more time Kerbin have to spin under you, "pushing" the destination a bit further.

My previous entry took ~50 Min, or ~3000 secs, to circumnavigate Kerbin. Well, If I travelled 5.860Km in 3000 secs, I had an average speed of 1,89333333 Km/Sec. What's impossible, because my top speed was 1,4 Km per sec! :D 

As in the previous post, Kerbin has ~3.770 kms on the Equator. Since the day on Kerbin is 6 hours, Kerbin "runs" 3.770 Km each 6 hours, or ~628.33 Km each hour, or ~174m/s.  Problem is.... At 174m/s, on 3.000 secs the distance covered is about 522 Kms, 25% of the difference between what KSP says I traveled and the circumference of Kerbin: 5860 - 3770 = 2090.

Furthermore, Forum says that the Kerbin's atmosphere rotates together the ground, so that 174m/s should not influence your travelling.

But so, why KSP says I travelled 5.860 Km? :P If someone has an explanation, I'm hearing! :)

remember your not at sea level. Adding your sea level altitude component to the radius of kerbin and calculating circumference from there might be of slight help.

Edited by Raptor kerman

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19 hours ago, Raptor kerman said:

remember your not at sea level. Adding your sea level altitude component to the radius of kerbin and calculating circumference from there might be of slight help.

But then this is not "Ground Distance Covered"!! It's "linear distance" or whatever, the ground below me doesn't "stretches" as I fly higher!

Anyway, let's check: C = 2πr ; r = C/2π;

C(Kerbin) = ~3.770Km; r(Kerbin) = ~600Km

C(Me) = 5860Km; r(Me) = ~932.648 Km

But I had flown at ~21Km high (average), or r(Kerbin)+21; or r(me) = 621Km.

So...

C(me) = 2π * 621 = ~3901.858Km , being this number that "linear distance" thingy I mentioned. It's merely a 131Km more than travelling on the ground, not 2090!

Edited by Lisias
Tyops galore! On my math!! AAAAARGH!!!

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On 1/4/2020 at 8:28 PM, ManEatingApe said:

Here is my compact entry in the Lightning division weighing only 10.6 tons (plus 6kg of snacks :)).

KTctwIm.png

Top speed was restricted to 2,670 m/s due to the limited heat tolerance of the Mk1 parts, but acceleration and braking was high due to the low mass.
The last minute pull-out of the dive when approaching the KSC was dramatic! Total elapsed time was 27:37.

A fun fact is that the entire journey was completely automated using a kOS script. If anyone would like to use the script and tweak it for their own entry then please feel free, source code is included in the spoiler below.

  Reveal hidden contents

@lazyglobal off.

// Desired cruising altitude and speed
local altitudeSetpoint is 34700.
local airspeedSetpoint is 2670.

// Save runway location so vessel can navigate towards it during final approach
local kscRunway is ship:geoposition.

// Mutable vessel state
local upsideDown is false.
local approachingKsc is false.
local stoppedAtKsc is false.

// Increase roll control threshold and response
set steeringmanager:rollcontrolanglerange to 45.
set steeringmanager:rollpid:kp to 1.6.

// Initialise PID controllers with constants tuned to a specific craft
local maxYawAngle is 4.
local minYawAngle is -4.
local latitudePid is pidloop(0.004, 0.000007, 0.0001, minYawAngle, maxYawAngle).
set latitudePid:setpoint to 0.

local maxVerticalSpeed is 450.
local minVerticalSpeed is -700.
local altitudePid is pidloop(0.25, 0.006, 1.6, minVerticalSpeed, maxVerticalSpeed).
set altitudePid:setpoint to altitudeSetpoint.

local maxPitchAngle is 17.
local minPitchAngle is -47.
local verticalSpeedPid is pidloop(0.5, 0.0002, 0.1, minPitchAngle, maxPitchAngle).
set verticalSpeedPid:setpoint to 0.

local maxThrottle is 1.
local minThrottle is -1.
local airspeedPid is pidloop(0.05, 0.006, 0.006, minThrottle, maxThrottle).
set airspeedPid:setpoint to airspeedSetpoint.

// Start
sas off.
brakes off.
stage.

//Create ascent triggers
when ship:altitude > 100 then gear off.
when ship:altitude > 20000 then upsideDown on.

// Create descent triggers once craft is far enough away from KSC
when kscRunway:distance > 200000 then {
    when kscRunway:distance < 180000 then upsideDown off.
    when kscRunway:distance < 134000 then {
        // Vesssel responds differently when lighter and in thicker atmosphere so tweak altitude PID loop constants
        set altitudePid to pidloop(0.5, 0.0002, 0.4, minVerticalSpeed, maxVerticalSpeed).
        set altitudePid:setpoint to kscRunway:terrainheight + 10.
        set airspeedPid:setpoint to 0.
    }
    when kscRunway:distance < 30000 then approachingKsc on.
    when kscRunway:distance < 6800 then {
        gear on.
        chutes on.
        brakes on.
    }
    when ship:groundspeed < 0.1 then stoppedAtKsc on.
}

// Main control loop that keeps vessel at desired heading, altitude and speed
until stoppedAtKsc {
    // Yaw
    local lateralDistance is kerbin:radius * constant:degtorad * (ship:geoposition:lat - kscRunway:lat).
    local compassDelta is latitudePid:update(time:seconds, lateralDistance).
    local desiredCompassAngle is choose 270 + compassDelta if approachingKsc else 270.
    // Pitch
    set verticalSpeedPid:setpoint to altitudePid:update(time:seconds, ship:altitude).
    local desiredPitchAngle is verticalSpeedPid:update(time:seconds, ship:verticalspeed).
    // Roll
    local desiredRollAngle is choose 180 if upsideDown else 0.
    set steering to heading(desiredCompassAngle, desiredPitchAngle, desiredRollAngle).
    // Throttle
    set throttle to throttle + airspeedPid:update(time:seconds, ship:airspeed).
}

 

Hi ManEatingApe, i have been trying to use your script to fly my plane but couldn't make it work. I edited the heading to 90 instead of 270. The plane take off just fine, then rise up arround 30-40 degree and slowly leveling up at 5000m then start heading down and crash. 

I know my plane got enough trust (4 rapier), why it start levelling up by itself while it have not reach the intented altitude? (34700 in your script.). Thanks.

 

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5 hours ago, OverClock said:

Hi ManEatingApe, i have been trying to use your script to fly my plane but couldn't make it work. I edited the heading to 90 instead of 270. The plane take off just fine, then rise up arround 30-40 degree and slowly leveling up at 5000m then start heading down and crash. 

I know my plane got enough trust (4 rapier), why it start levelling up by itself while it have not reach the intented altitude? (34700 in your script.). Thanks.

Hi @OverClock, welcome to the forums and to this challenge!

Quick forum tip: You can type an "@" symbol to mention a forum user by name. A little box will popup that searches forums users as you type. That user will then receive a notification the next time they login that you mentioned them and their name will be outlined in blue (just like yours above).

Regarding your plane, there any many things that could be going wrong - COL ahead of COM, insufficient control authority, script needs tuning.
In order to help you I'll have to see pictures of the plane or better yet the craft file itself.

The forum doesn't allow uploading files directly, so you'll have to use an image sharing site such as imgur.com and a file sharing site such as dropbox.com or Google Drive.
So I'd suggest you do the following:

  • Upload a screenshot of your craft to Imgur
  • Upload your craft file to Dropbox
  • Post to this thread including both these links (you can use the "Insert image from URL" button to display an image inline)
Edited by ManEatingApe

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Hi @ManEatingApe, thanks for the reply.  I have uploaded my plane to google drive, here is the link https://drive.google.com/drive/folders/1xiIxmVsjOt6IJWMg1qiyYz8ScMUEYRvf?usp=sharing

D4rbrY7.png

 

if i fly manually, i can reach the intended altitude just fine.

1VunoDv.png

where did i do wrong? Its same script, i just change the heading to 90 instead of 270. I am to lazy to rotate the plane on the runway.  (Btw i did try to rotate the plane and use exact same script, same result though).

Thanks!

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:rep: ATTENTION ALL FLIERS :rep:

 

This is just a reminder that the deadline to submit entries is only 18 days away (specifically, February 20, 2020 at 11:59 pm Eastern Standard Time). If you want to "get high on speed," simply hit the SPH, get your camera ready, and start your engines. As for the entries that have already been submitted, great job.

  • I'm even more impressed with you all discussing strategies and helping each other out.
  • Even for those who just showed test runs (and not official submissions), I'm glad to see that you're taking this seriously.
    • If at first you don't succeed, try try again.

 

And now, the numbers you've all been waiting for. If you think any of them are wrong, or if I'm missing something, just tell me and I'll address it.

  • And before you ask, for mass divisions, I'm more interested in starting mass because that's easier to obtain.

 

CURRENT LEADERBOARD

  1. LIGHTNING DIVISION
    1. @ManEatingApe - 27 minutes, 37 seconds
    2. @nelso - 35 minutes, 18 seconds
    3. @vyznev - 35 minutes, 18 seconds
    4. @Laie - 39 minutes, 47 seconds
    5. @Lisias - 50 minutes, 15 seconds
    6. @Mars-Bound Hokie (ME) - 53 minutes, 18 seconds
    7. @Nantares - 57 minutes, 47 seconds
  2. THUNDER DIVISION
    1. @Laie - 24 minutes, 32 seconds
    2. @nelso - 28 minutes, 45 seconds
    3. @AHHans - 52 minutes, 54 seconds
    4. @Lisias - 54 minutes, 44 seconds
  3. HEAVY RAIN DIVISION
    1. @nelso - 29 minutes, 45 seconds
    2. @έķ νίĻĻάίή - 63 minutes, 48 seconds
    3. @Klapaucius - 72 minutes, 6 seconds

 

@Turbofreak, I can't see your pictures on your entry. Have you tried saving them on Imgur and posting links?

070TW4J.png

 

One more thing I would like to tell you all about. Yesterday, I started a "sister challenge" for all you spaceplane buffs and Laythe enthusiasts. If you haven't already guessed, the name of the game is "Around Laythe in 80 Minutes." Feel free to take a look and/or join. 

 

Keep up the good work, everybody. Don't text and fly.

Edited by Mars-Bound Hokie
Grammatical error

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1 hour ago, OverClock said:

D4rbrY7.png

9 hours ago, ManEatingApe said:

Regarding your plane, there any many things that could be going wrong - COL ahead of COM, insufficient control authority, script needs tuning.

Took your craft for a test spin, problem is: script needs tuning to match craft (or alternatively craft needs tuning to match script :))

My craft was borderline unstable i.e COL and COM were very close. This made the craft very maneuverable and enabled the wacky acrobatics that the script depends on.

Your craft is very very stable, I can see from the screenshot (and messing around in the VAB) that COM is very far ahead of COL.
This is great for stability but means the craft reacts slower.

2 suggestions:

  • Adjust script: Change the line set steeringmanager:rollpid:kp to 1.6. to set steeringmanager:pitchpid:kp to 5.0.
    Your craft has plenty of roll authority but the slow reactions mean that more aggressive PID control is needed.
    I did a test flight with a value of 5. The craft no longer crashed into the ocean but overshot the max altitude so you will still need to tweak this value.
  • Adjust craft: Move the side pontoons forward or adjust your wing shape to make your craft less stable and more maneuverable.

Unrelated to stability I would also suggest waiting to stage your nuke until at least 10,000 meters altitude. Below that altitude ISP and thrust is low, so you're wasting fuel.

Edited by ManEatingApe

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@ManEatingApe I had to move the COL wayyyy back to make it stable, i can't even fly the plane if COL is near COM. How do you manage to fly borderline stable plane? I clearly have a lot to learn.

I have try several KOS script, but i like yours because it looks so much simpler and efficient. But i really have problem understanding them, set steeringmanager:pitchpid:kp to 5.0 seems to solve the crashing problem, but why? 

Would you mind sharing your wisdom to us beginners how it work? maybe start a new thread especially for that? I believe a lot of us beginners are struggling to use KOS script. I try google "set steering to heading" but cannot find other script that use that command (not even in the KOS documentation), most script use LOCK steering to heading. :confused:

 

 

Edited by OverClock

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Alright, i tried this to be official, but sadly a Rtg overheated and an airbrake, in the final moment it ran out of gas, for two seconds i passed the limit altitude, I had to do an emergency landing close to the KSC due to the lack of gas, landed smoothly, then the kraken made it drift and crash.

Well, im submitting this as unofficial,

d6yJscC.jpg

Imgur album

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