One Juno Circumnavigation!

[Watermel00n]

RULES!

Spoiler

1. Only ONE JUNO engine

2. You have to fly in one direction without changing.

3. No refueling allowed.

4. Drop tanks are okay!

5. End where you start!

6. No leaving the atmosphere.

7. Your aircraft must contain 1 or more wing parts

 

 IDEAS

Spoiler

Example of a  long-range 1 juno plane. Keep the drop tanks near the CoM.

 

SCORING:

Spoiler

Easy - Complete an unkerballed circumnavigation

Medium - Complete a 1 kerbal circumnavigation

Hard - Complete a 2+ kerbal circumnavigation

If you complete more than 1, there will be a x___ at the end. E.g. Medium x2

BADGE!

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Winners!

Easy

Spoiler

 

Medium

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@swjr-swis- Compact little plane. I like the basic fins that make it seem like an early career game.

@camacjux7 - Streamlined fairing reduces drag and allows the plane to circumnavigate at supersonic speed!

Hard

Spoiler

@CFYL- Futuristic design and interesting wing layout makes this design stand out. It also holds 2 kerbals! 

Good luck!

Edited May 26, 2022 by Watermel00n

[Kerb24]

Interesting.

[Watermel00n]

i just realised that landing is ok so will allow it as long as no refuel 

[Rutabaga22]

This seems awesome! Will do.

 

[Rutabaga22]

I have a staged thing that only uses 1 juno at a time. Is that OK?

[Rutabaga22]

None of my planes are stable. 

I give up

 

[Watermel00n]

I jave some design idea, will show tmr. Don't give up!

[MythicalHeFF]

Is there going to be any sort of scoring system or categories (i.e. lowest mass or doing multiple circumnavigations)?

[Watermel00n]

Good idea.

[camacju]

I got eight laps around Kerbin but I misread the rule that required only one Juno engine. A few hours wasted - back to the drawing board...

[Rutabaga22]

could some, say, make a one juno ssto and do a full orbit?

[sevenperforce]

Can you add propellers if they are powered by the Juno's alternator? Like a turboprop?

[Watermel00n]

Erm, no. Only thrust comes from the Juno.

2 hours ago, Rutabaga22 said:

could some, say, make a one juno ssto and do a full orbit?

Remember rule 6 but if you don't leave the atmosphere, I don't see what's wrong with that.

[Bej Kerman]

On 5/22/2022 at 2:11 AM, Watermel00n said:

6. No leaving the atmosphere.

May I ask why not?

[Watermel00n]

9 hours ago, Bej Kerman said:

May I ask why not?

People could send an aircraft into space and skip on the atmosphere.

[Bej Kerman]

1 hour ago, Watermel00n said:

10 hours ago, Bej Kerman said:

May I ask why not?

People could send an aircraft into space and skip on the atmosphere.

Isn't that a good thing?

[swjr-swis]

Ok let's start you off with a lightweight entry, the MinCN-1885

The MinCN-1885. 16 parts, 1.885 t, single Juno, single seat.

Jeb standing ready, all of 91 units of LF in the tanks.

Cruising mach 2 @ 11.5 km.

Halfway point.

One full circumnavigation later, back at the KSC runway.

Full album: https://imgur.com/a/bRtYrpu

[CFYL]

Warning: this spoiler is image heavy.

Spoiler

Plane at the runway. Why do you drop tanks when you can absolutely make a "normal" plane?

takeoff, holding 2 crew.

Say goodbye to KSC

Spinning out of control 16 minutes after takeoff. Luckily we have enough altitude to save this small plane.

Stable again -- we lost 1000m altitude and was on the brink of a crash. But we managed it without using much fuel.

Sunset.

I kept throttle low. The slower we fly, the less drag we experience. 

Sunrise.

I don't have autopilot mods. So I simply manually pitch down now and then and let the curvature of Kerbin pitch the plane up.

It is boring so I'm actually using my brain on school stuff while KSP is running. Just pressing S now and then. And a big surprise came, when I was working with a pen and paper... The plane flew ovew a mountain. It was less than 300 meters from the highest terrain. If it crashed, I can't quickload!!!

Still proceeding.

Flew into another night... The cruising altitude^* has raised from 2000 to 3000. ^*cruising altitude is like the average, cuz I can fly to 4km with 80m/s speed and pitch down, then going down to 1km with almost 200m/s speed before curvature pitches the plane up.

We are officially 62.5% across the Kerbin surface. Fuel reserves look good.

Sunrise. Cruising altitude has raised to 5km. throttle up because I am near the big crater. I can't crash.

Fly past the crater's mountains.

It looks like this from the bright side.

Last sunrise in our route.

We are now officially 75% through the trip. We "should" have 660×0.25 = 165 units of fule left, but we have more.

Flying past the desert.

The only mountain ahead is the one adjacent to KSC.

We are really near KSC.

Let the last glows of Kerbol carve out the plane's shape.

We can see the KSC lights. Over the long journey we went a bit off course. We flew a little bit to North so we have to fly south.

trying to have visual of the runway. I suck at landing --- and this is a night landing!

Missed the runway. Pitch up and try again. Yes, If I had touched down successfully, I could have 101 units of LF left. But I suck at landing.

Trying to approach the runway...

OK finally came to a complete stop.

This is how I put Jeb ad Val in the plane...

Actually, I interpret this challenge as "build a plane powered by a single Juno, that can fly some 1885km(equatorial circumfrence of Kerbin. This coincides @swjr-swis's mass!) without refueling". So this is how I did it --- a plane whose stall speed is less than 40m/s but reaches 200m/s during flight. Its average speed is some 304km/h, about the same as a bullet train IRL.

Now I hope I haven't violated the spirit of this challenge

On 5/22/2022 at 9:11 AM, Watermel00n said:

2. You have to fly in one direction without changing.

because I actually flew with heading between 89-91 degrees during most of the flight. But my plane has spun out of control twice, and the final approach was a southeastern flight. So the HDG actually ranges between 0 and 360 degrees

But this is my first time to actually complete a circumnavigation in the atmospere! (in vacuum, we have a fancy name for circumnavigation called "orbit")

craft file: https://kerbalx.com/CFYL/Juno-Ciucum

[CFYL]

Sorry.

1.  The equatorial circumference is twice of 1885km -- C = 2πR and I forgot the "2".
2. I use mods -- Waterfall & StockWaterfallEffects. Both are aesthetics mods and should be fine.

[swjr-swis]

22 minutes ago, CFYL said:

that can fly some 1885km(equatorial circumfrence of Kerbin

Psst: double that. 2 π * 600 km radius. Actually 607 km, unless you plan to phase through mountains.

[camacju]

I probably put way too much thought into this flight.

In KSP, engines have a specific impulse - they consume fuel for a given thrust. Since work=force*distance, power=thrust*speed, so for a given thrust we want to be flying as quickly as possible.

This means minimizing drag. And since the Juno has low thrust, this also means not including as much fuel as I can physically take off with. If I do that, I get stuck around the sound barrier and have to eat a very big lift to drag penalty.

Interestingly enough, the Juno tops out at around Mach 2.05, which also is near a peak in lift to drag ratio. So this is my desired flight regime.

Craft in SPH. One Juno, one control surface, and as much fuel as I can pack while still being able to go through the sound barrier.

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On runway

Accelerating at sea level

Climbing slowly while pushing through the lift to drag minimum at Mach 1.1

Through the sound barrier, accelerating at a slow climb

At this point, I point near the horizon and don't try to manage altitude or thrust at all. Full throttle is better because I can fly faster and at a point farther to the right on the Juno's thrust curve, which increases specific power output of the engine. I just keep a -1 degree angle of attack for maximum L/D and let the aerodynamics balance themselves out - it'll naturally balance at the correct point  where the Juno's thrust is just enough to overcome drag, which is also the maximum speed it can attain for a given mass.

Spoiler

Accelerating

Lap 1

Lap 2

Lap 3

Lap 4

Lap 5

Lap 6. At this point I'm not sure whether I'll have enough fuel for a seventh, but I attempt it anyway.

Cutting engines over the K2 mountain range

Descent

Landing

Final result - 7 laps around Kerbin, single kerbal craft

[Watermel00n]

@swjr-swis @CFYL @camacju

Here's your badge!

I updated the leaderboard.

[zolotiyeruki]

Ok, as a moderator for a previous circumnavigation challenge, I feel like I need to lawyer this one a bit:

1) Do we have to hold a Kerbal?
2) Only one Juno, but are other engines allowed?
3) camacju's entry uses a neat exploit that drastically reduces drag.  Is that allowed?

[Watermel00n]

10 hours ago, zolotiyeruki said:

Ok, as a moderator for a previous circumnavigation challenge, I feel like I need to lawyer this one a bit:

1) Do we have to hold a Kerbal?
2) Only one Juno, but are other engines allowed?
3) camacju's entry uses a neat exploit that drastically reduces drag.  Is that allowed?

1. Depends on the difficulty level.

2. No

3. Yes