gilflo

Long distance Naval contest with Gliding Dolphin

12 posts in this topic

Posted (edited)

Hello

Here is my report from the challenge you can find here: It's a speed boat challenge mixed with discovery

Looking at what have been done with boats, speedboats, and hydrofoil, i found it would be very difficult to built a boat with foil. To get get max speed on water, the idea is to lift up the hull and to get a minimum surface in contact with the water...It can be achieved with foil but I decided to try another way: I would try to lift the boat with wings, the challenge being not to take off....

Here is the design of the Gliding Dolphin: A catamaran with mk2 tank floating hulls, the hulls being on the minimum surface side and the deck, each side of the cockpit and the passenger cabin, being a wing. The engines are 2 Wesley J-33.

The catamaran contains 9600L of liquid fuel and the fuel partition is made so that the center of mass won't move whatever is the fuel quantity. The Center of lift is just some millimeters behind the COM....When testing the boat, 1 or 2 mm more afterward or more ahead could make speed fall from 10m/s, so I needed many tests to get the best design. the wings also are lower at the back of the boat and and higher at the front, helping for lift, as the boat can move on its pitch axe.

So speed at maximum weight and full throttle is 56m/s, it reaches 137m/s when 40% fuel left, and if you go higher you loose control, so when 40% fuel left you must begin to lower throttle. 

To avoid pitch oscillations on water I use SAS and Pilot assistant which uses 2 ailerons at the end of the wing to maintain a Vertical speed of 0. They acts like elevators that would damp pitch oscillations, helping to increase speed and not to take off at high speed.

Here is the boat. it's equipped with 4 retractable gears to help to beach and to help braking in water by means of their drag

688021screenshot68.png

The contest: The goal is to discover and name 10 places and come back to Kerbin, as fast as possible and without refueling. there's 2 pilot and 8 passengers on board. Estimating the range of the boat, I identified, on Kerbin Google map, 10 places with their coordinates and waypoints between them to calculate the exact distance of the challenge.

 

Spoiler

650314Glidingdolphinplannedtrip.png

Here are the first 3 places we will visit: Seagull Island North Cape, Penguin Island and Pirates Cape

Spoiler

489693GoogleKerbin.png

I will use Waypoint Manager and Scansat Map to navigate the places. Departure from Runway 27

Spoiler

183169screenshot69.png

Watering

Spoiler

125940screenshot70.png

We leave Jeb island on the right, heading to our first place, seagull island North cape, some 300 kms east of Kerbin base

Spoiler

177482screenshot71.png

Half way, we can see the island on the map

Spoiler

771349screenshot73.png

We can timewarp 2 ou 3, provided the pitch oscillations are dampened by Pilot assistant, which requires fine settings. If settings are bad, time warping make pitch oscillations happened and breaks speed and range

Approaching our first islands

Spoiler

396494screenshot76.png

After this waypoint, we turn right to our Seagull Island North Cape where we will stop. If we can't beach, a passenger will swim to the island and plant a flag to name the place.

Spoiler

999462screenshot77.png

Stopping just in front of the shore. It's toos steep to beach

Spoiler

801542screenshot79.png

Degy Kerman is planting the 1st flag after a great climb

Spoiler

376635screenshot83.png

Degy Kerman is returning to the boat. For all the places, the coordinates have been found by studying a HD Kerbin map on Google map, but the coordinates of the point gave it 685m ahead in the land. The purpose was to to give rough coordinates, so for the next point we will correct them if the point is too far in the land or in the water....

Spoiler

314746screenshot84.png

Climbing on board after a short bath

Spoiler

550964screenshot86.png

Here is our EVA time for the contest

Spoiler

222655screenshot87.png

Leaving for the next place which is an island very near from here

Spoiler

899461screenshot89.png

Here is Penguins island, no penguins here, but the waypoint is in the water, so we will plant the flag on the beach. Night has fallen

Spoiler

266342screenshot92.png

Lula Kerman plunging in the water

Spoiler

504857Screenshot92A.png

And planting the flag

Spoiler

779214Scrennshot92B.png

EVA time of Lula for the contest and we can also see the max speed achieved, the global distance being not right....

Spoiler

939346screenshot94.png

And we leave for a night trip for the next place, Pirate Cape, some 300 km in the north east. Easy to manoeuver, the J-33 can be reversed...

Spoiler

547527screenshot97.png

Approaching Pirate Cape, a little bit more than 50% fuel left and you can see speed is 99

Spoiler

133399screenshot100.png

Near the beach at 100.9m/s, our max speed on this trip, and time to throttle down!!

Spoiler

611152screenshot102.png

Tanda Kerman is planting the flag. We corrected the coordinates, the point being 900m farther in land

Spoiler

732337screenshot104.png

Back on board

Spoiler

427450screenshot105.png

EVA time for Tanda. Note that the max speed indicated is false. 169m/s is impossible. I don't know were is the trick..!! Our max speed was at 3 kms from beach, 100.9m/s

Spoiler

669640screenshot108.png

A vid to follow

Edited by gilflo
1 person likes this

Share this post


Link to post
Share on other sites

Posted (edited)

WOW, that is a lot of work you put into this, great job!:wink:

Edited by Alpha 360
"Kouston, we have several problems, but that doesn't matter so we want to continue on with the mission."

Share this post


Link to post
Share on other sites

Excellent start. I'm following along on a map a have, and I am very impressed. I made some estimates on your ranges based on the images you posted, and I get a max range of around 2120km, but it's based on only three data points :) . I'm hoping you'll be able to squeeze an additional 900km out to get back home.

That range completely blows away the ship that I had that is closest in fuel capacity to the "Gliding Dolphin". My "Western Nosebleed" had 11,125L of fuel and only had a range of 1,219km. That means you doubled the range with less fuel. Super cool.

Looking forward to the next leg of the trip, and am _really_ looking forward to playing with the craft file. That is a great design and I'd love to include the cargo bay ability mine have to transport submarines and runabouts. 

Share this post


Link to post
Share on other sites

Posted (edited)

Well here is a short vid

Range versus fuel left in percent

820842Capturedcran20170508231102.png

The range stays between 1150 and 1250 kms. 

Notice that following my tests maximum control speed, 137 m/s is achieved around 45% Fuel left at max throttle, then we should keep this speed until 20%, Throttle decreasing progressively to 1/2.

So between 45 et 20% fuel we got 137m/s at an average 2/3 throttle, then under 20% fuel left we must reduce throttle to 1/3 for an average speed of 115. Boat is toop light and difficult to control, so speed must be decrease.

So far we have 742 kms and there's 54%fuel left, with an average speed of 78m/s and range is still around 1250 kms. so it makes 2000, but from now we should increase average speed by 50% and reduce throttle by 50%, which should increase dramatically the range. Anyway, I set 2 more places that will not flag (12 places for 10 people) at the end of the trip and if i see i don't get enough range i can make a short cut to the base..

Edited by gilflo
1 person likes this

Share this post


Link to post
Share on other sites

Posted (edited)

Hello

Here is the next part. This where it becomes very interesting because, du to the design, when the boat is light enough, under 55% fuel, playing with the setting of the the flaps at the rear of the "wing deck" which are no more than elevators, and playing with throttle, you can lift the hull so that the boat is just sliding or gliding (i don't know the right english word) on a the water just on the "slice" of the hull. And the good news is that you can do this at timewarp 2.

The trick is to go full throttle until the hull lift to 2m and the speed is 130m/s increasing, then you must reduce THR, depending on you weight, to nearly 1/3, 6/15, and keep speed between 130 and 140. doing that, the range increases dramatically as we can see on the picture. To do this Pilot assistant is needed as it's the only way to play very accurately with elevator setting by the means of the vertical speed .

211247Capturedcran20170511164253.png

Between 55% and 40% fuel left, i played with the VS setting, asking 0.025 to 0.022 m/s to help lift off the hull. So you play with THR and VS to keep your speed between 130 and 140, but as there's no THR setting by 1% you can't stop playing with the throttle during all the trip to keep your range as high as possible.

We leave now Pirates Cape by night

Spoiler

277333screenshot1091.png

playing with the engines power to turn quickly

Spoiler

269898screenshot1092.png

VS setting is set to 0.03, fuel left around 50%, and we can reach 120m/s

Spoiler

680615screenshot111.png

Day is rising as we are approaching WPT 7. 

VS is 0.022, speed 134 and THR between 11/15 and 12/15, fuel left 45%, range is 4:05, meaning we leave our 1200-1300kms range we had until now for 1900-2000 km

Spoiler

399721screenshot114.png

Sun rise passing WPT 7

Spoiler

231052screenshot117.png

We beach in a bay and name our bay "Crystal Canyon mouth"

Spoiler

831554screenshot118.png

Leggy Kerman plants the flag

Spoiler

555180screenshot121.png

Why is it called Crystal Canyon? I went through the canyon during my Elcano Challenge. Water is Crystal water all along the canyon

Spoiler

644420screenshot724.png

Here is the photo for the Mission time, but only mission time is right,I saved the game, forgot to take a screenshot, continue the mission, then came back for the screenshot by loading the game...

Spoiler

355783screenshot12111.png

Departure to Lodnies island

Spoiler

589761screenshot124.png

See speed and THR settings approaching WPT 9. Range is more than 1D 1H !!!

Spoiler

666754screenshot127.png

We need to turn right to 353° to head for Londres so we must  slow down under 80 to avoid crash or breaking one of our front nose cone tanks

Spoiler

333867screenshot129.png

You can see here how we are sliding on the hull slice (on the black band which is at the very bottom of the hull, at 136m/s THR 6/15 and Range >1D

Spoiler

130912screenshot133.png

Approaching Londnies island

Spoiler

539168screenshot137.png

It's not beach as I believed, but cliffs!!

Spoiler

453790screenshot139.png

The boat is nearly beached

Spoiler

767687screenshot140.png

and Manus kerman disembark and climb a little bit to plant a flag

Spoiler

832108screenshot147.png

Back to the boat, 30° slope, easier to go down!!!

Spoiler

445976screenshot148.png

5H15mn up to Londnies island, photo taken after loading game, because I forgot it

Spoiler

869744screenshot151.png

Same with no F3. Everybody is on board, ready for departure.

Since our Departure we have done 1415 kms in 5H15, nearly half way, which gives an average speed of 74.86m/s and we have now enough range to achieve our trip at maximum speed of 137-140m/s. so we can plan an average global speed of 100m/s

Spoiler

919203screenshot150.png

Here you can see the boat in the SPH and what I did to avoid flipping or take off, or to avoid it as long as possible.....The torque at full weight gives a maxi pitch downward momentum. The momentum decreases as weight decreases which explain why i must be very accurate on elevator setting for VS.. i should have done the opposite, there's no chance to flip or take off when the boat is heavy, but with the design, if I set a null momentum at heavy weight, at low weight there's a pitch up momentum.......

Spoiler

192246screenshot142.png

Short Vid: departure from Pirates Cape and arrival to Lodnies Island with a part where we can see high speed THR 

 

Edited by gilflo
1 person likes this

Share this post


Link to post
Share on other sites

My new max range calc is 2960km, so wooo! Go go go!

 

Share this post


Link to post
Share on other sites

Posted (edited)

Continuation of the trip

Leaving Londnies island, time Day 1 05H15mn

Spoiler

324161screenshot156.png

We got 37.8% fuel left and next point is Heavens bay south, 287 kms ahead. Fuel is balanced, SAS on and VS 0.022 selected

Spoiler

617238screenshot162.png

Accelerating along Island, THR decreasing

Spoiler

947125screenshot169.png

Approaching 140m/s i decrease THR slowly and try to get the best setting according to the VS setting,  which is not obvious, a few % less and the hull don't skid anymore on water and the speed drop dramatically....

Spoiler

269156screenshot171.png

finest setting and you can see the bottom of the hull is really skidding on the water surface. if we go to fast or if the VS setting is not accurate enough, the boat can really fly and it wouldn't be a boat anymore....

Spoiler

682373screenshot173.png

80 kms from Heavens bay and you can see how little fuel we spend on this trip...

Spoiler

789211screenshot181.png

14 kms from beach. Heavens bay latitude is only 28N but you can see in background a mountain glacier which is around 75N latitude...

Spoiler

276680screenshot186.png

We just stopped on the beach, hulls rubbing the sand. as you can see Fuel left is 34.4 which means we used 3.5% fuel for a 290km trip, 

3.5% of 9600L is 336L, which means we spent around 1.15l/km, so with 34.4% fuel left our range should still be around 2600 kms

Spoiler

550597screenshot190.png

Flag planted

Spoiler

169029screenshot192.png

Time photo for this N°6 point

Spoiler

618109screenshot194.png

Here is an Excel sheet from our range calculated at 35% with a 137m/s. But dam not sure we can keep this high speed at lower weight.

Spoiler

548701Capturedcran20170516122505.png

Leaving for Hell's point, short distance. We use reverse power to leave the beach

Spoiler

971106screenshot197.png

Heading South east, there's a waypoint to pass across a cape, before Hell's point. You can see the white mountain of North pole in back ground

Spoiler

601730screenshot200.png

Waypoint 10 is passed and we have to throttle down under 80 to turn without danger...

Spoiler

817824screenshot202.png

47 kms from Hell's point, THR stiil 1/3, VS is between 0.025 and 0.03, that's why we see 0.03

Spoiler

577064screenshot204.png

Beach again, Hell's point is 435m away in water, so we will plant the flag and correct Hell's point coordinates

Spoiler

563395screenshot206.png

Flag N°7 planted

Spoiler

348508screenshot209.png

Time photo: Day 1 00H28mn

Spoiler

953756screenshot210.png

Departure for Sanctuary Mouth Lagoon. There's a few waypoints to navigate along the shoreline and through islands...

Spoiler

255969screenshot213.png

Approaching Waypoint 11

Spoiler

379444screenshot214.png

Approaching Waypoint 12

Spoiler

933619screenshot217.png

Heading to Waypoint 13

Spoiler

967183screenshot220.png

Heading to Waypoint 14

Spoiler

142667screenshot224.png

Beach at Santuary Mouth Lagoon

Spoiler

804327screenshot227.png

Flag point N°8 planted

Spoiler

399241screenshot228.png

Time photo Day 1 01H01mn

Spoiler

931940screenshot229.png

 

Edited by gilflo

Share this post


Link to post
Share on other sites

Posted (edited)

Last 2 points to name and flag.

Leaving sanctuary mouth to West indies cape

Spoiler

740742screenshot239.png

On course to WPT 15, there's a lot of waypoints along the shore to west indies cape

Spoiler

563771screenshot241.png

Passing waypoint 15

Spoiler

587377screenshot243.png

On course to waypoint 16, max speed 140, THR  1/3, still more than 27.5% fuel, notice our range is still more than 5H at this speed

Spoiler

260274screenshot247.png

Proceeding to waypoint 17

Spoiler

689849screenshot252.png

Approaching West Indies cape

Spoiler

292109screenshot261.png

Beached

Spoiler

659886screenshot262.png

Naming and flagging the point

Spoiler

765783screenshot263.png

Back on board

Spoiler

908117screenshot264.png

Time photo

Spoiler

653140screenshot265.png

Leaving West Indies Cape

Spoiler

543507screenshot267.png

Sun will soon disappear

Spoiler

464516screenshot269.png

We are very light with less than 25% fuel and i throttle carefully to increase speed...It looks like it's better to set again VS to 0.03

Spoiler

428285screenshot271.png

Maxi speed 130 on course to waypoint 20

Spoiler

368257screenshot273.png

Passing WPT 20 and slowing down to turn to Withsunday Entrance point

Spoiler

552463screenshot275.png

124 kms from entrance. Playing with throttle to stabilize speed as VS oscillations decrease

Spoiler

155944screenshot276.png

Night is falling as we are approaching the entrance of the bay, throttling up after route correction

Spoiler

811576screenshot279.png

Turning in the bay to reach the beach

Spoiler

374531screenshot284.png

Beached

Spoiler

838679screenshot287.png

Last point named and flagged

Spoiler

998447screenshot288.png

So far, 7H55mn for a 2562km trip , and distance to finish is 438 kms which is a piece of cake as we got 20% fuel left.

Spoiler

998447screenshot288.png

 

Edited by gilflo

Share this post


Link to post
Share on other sites

Posted (edited)

To the end of the challenge

Juste remind the trip, here is the pic of the trip measured on google earth. if we divide the distance by 10.64 we get 2998 kms, I would say + or - 10 or 20, because sometimes the waypoints coordinates found on google earth put the waypoints 500m to 1000m in the land.

Spoiler

650314Glidingdolphinplannedtrip.png

Now we leave Withsunday bay, using engine reverse, fuel left is 21.6%

Spoiler

590800screenshot291.png

Heading out of the bay, before turning right to our next waypoint: Withsunday Cape

Spoiler

913655screenshot292.png

VS setting has been set to 0.022 and we are turning on course to Withsunday cape

Spoiler

307600screenshot293.png

Timewarp 2 i try not to speed over 123

Spoiler

386972screenshot294.png

 because when throttling down it sometimes flips like that

Spoiler

741458screenshot298.png

And the boat suddenly pass from 120m/s to 0 without breaking if you're lucky. Breaking a nose cone would be very annoying because not only you loose speed but the boat steers  non symmetrically........

We are approaching with sunday Cape and we will only turn along the shoreline as we can't disembark to name and flag the place, 10 places having been named yet.

Spoiler

147451screenshot295.png

Leaving with sunday Cape to Jeb Island south beach

Spoiler

509997screenshot299.png

Approaching Jeb Island we realize we are heading to the coast, we should have selected Waypoint 22 to pass along the east coast

Spoiler

246978screenshot302.png

To WPT 22 along the east coast

Spoiler

736293screenshot304.png

Heading now to the bay which is 60 km North east of the base, we are sure to make it with at least 15% Fuel left.

Spoiler

331331screenshot306.png

Max speed reached on a moment of carelessness, we quick set the throttle to 3.5/15 to decrease speed

Spoiler

202795screenshot308.png

A brutal stop reminds us to be more cautious on speed

Spoiler

174327screenshot311.png

Approaching bay entrance

Spoiler

612834screenshot316.png

Turning in the bay to our next waypoint

Spoiler

531377screenshot320.png

Throttle up in the bay

Spoiler

683758screenshot322.png

On course to Runway 27 entrance where we began the contest

Spoiler

443634screenshot325.png

Approaching beach carefully, the gears being not so strong

Spoiler

607943screenshot326.png

On the Runway 27 with 16.3% fuel left and notice we broke the left nose cone entering the runway.....But we don't need it anymore!!

Time is day 1 3H50mns

Spoiler

808695screenshot327.png

Final pic

Spoiler

210914screenshot329.png

So we did it in 9h and 50mn, that is 35429s which is an average speed of 84.62m/s

We used 83.7% of the fuel, which is 8035L. Our average specific range is 2998/8035 is 0.373, which means 0.373km by liter of fuel

Maxi range using all the fuel should theoretically be: 9600 X 0.373 = 3580kms

 

 

Edited by gilflo

Share this post


Link to post
Share on other sites
1 hour ago, gilflo said:

So we did it in 8h and 50mn, that is 31800s which is an average speed of 94.27m/s

We used 83.7% of the fuel, which is 8035L. Our average specific range is 2998/8035 is 0.373, which means 0.373km by liter of fuel

Maxi range using all the fuel should theoretically be: 9600 X 0.373 = 3580kms

 

 

Isn't it 9hrs and 50min? 1day 3hrs 50min 29sec = 6hrs+3hrs  50min  29sec = 32609sec. I'll update the main thread in a few minutes. Very excellent job!

Share this post


Link to post
Share on other sites

Posted (edited)

You're right, i updated it but it's 35429s

Edited by gilflo

Share this post


Link to post
Share on other sites
2 minutes ago, gilflo said:

You're right, i updated it but it's 35429s

Duh. You're correct. Math is hard apparently. Need coffee

 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now