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[DougMRC]

 PT109 US WW11 MTB (J F Kennedy) (1.8m in length) Built with Marine Ply, The plans were purchased from America and enlarged by 25%, it was then thought to be too big for brushed motors so an all brushless system with 3 brushless motors and 3 x 5 blade propellers have been installed running on  2 x 60A and 1x 90A Esc’s and powered by 2 x 11.1V and 1 x 22.2v lipo batteries.
At full speed due to its weight, power & speed she creates a bow wave in excess of 2M on each side
It has a working satellite navigation system that is also recorded on a camera and transmitted to the base station in real time.
The model is fitted with a self retracting tow line on the bow and a float free Gemini connected to the vessel by a 20M 100kg nylon cord for recovery purposes.
She can be seen on YouTube --- https://youtu.be/L0_XyZ7ChbE?si=d6VmNMxS5l52u4zi

[Akira]

You have done well. However, your bow wave shows the issue. Your weight distribution is WAY too far forward. Your hull is not getting up onto plane.I have a 5 ft ELCO ( PT 109 is an ELCO, same hull), and all of my batteries ( primary weight source) are aft of the hull midpoint, in fact two are mounted at the transom. Depending upon what you are using for batteries will effect your placement, but you really need to move or add weight aft.That will hopefully allow her to get up on to plane and much of the ploughing bow wave will disappear. I would suggest marking the waterline with painter's tape( it will come off easily) and attempt to trim the hull accordingly. I found that with the stern (and the rest of the hull)  at the designed waterline, my hull easily came up onto plane, even with only two of three motors running.
Good Luck

[dodgy geezer]

PT109 US WW11 MTB (J F Kennedy) (1.8m in length) Built with Marine Ply, The plans were purchased from America and enlarged by 25%, it was then thought to be too big for brushed motors so an all brushless system with 3 brushless motors and 3 x 5 blade propellers have been installed running on  2 x 60A and 1x 90A Esc’s and powered by 2 x 11.1V and 1 x 22.2v lipo batteries.
At full speed due to its weight, power & speed she creates a bow wave in excess of 2M on each side
It has a working satellite navigation system that is also recorded on a camera and transmitted to the base station in real time.
The model is fitted with a self retracting tow line on the bow and a float free Gemini connected to the vessel by a 20M 100kg nylon cord for recovery purposes.
She can be seen on YouTube --- https://youtu.be/L0_XyZ7ChbE?si=d6VmNMxS5l52u4zi

Interesting. How much does she weigh?
She seems to be doing about 3-5mph - which is about the right calculated scale speed for a 1:13 scale PT Boat, but planing craft should ideally be run at enough speed to get them up on the plane (usually about 10mph), and these shots still show it as running as a displacement hull. The full-size ones used to have their bows clear of the water.

5-blade props seem a little excessive for brushless, which like to run at fast RPMs - though we don't know their diameter or pitch, of course. What KV are your motors? And can you measure the actual RPM achieved?  How hot are the motors after a high-speed run?  11V is probably not going to put much power out, but the 22V motor will need checking to ensure that it does not overheat. I suspect that you might do better with 3 1.5"-2" X-type two blade props...

[Akira]

I agree with the Geezer, ELCO's has three bladed props, all were left handed. I think they were around 30 inch diameter. I think mine are 1 1/2-1 3/4 inch diameter.
I would suggest that you determine what the rated rpm of your motors is, and attempt to prop the boat to that rpm.
Bye the way, you motors will probably get warm-hot. Reason: no airflow over them to cool them as a plane would provide. You might consider water cooling if the motors run hot.But first, get her into trim.

[Backerther]

Hi
It's so surprising to know that you have built so large a MTB PT-109 with many hi-tech equipments aboard her.!!
And I have also enjoyed your short clip of the first sailing test very much on which I have some impressions as follows;
1) She did not successfully build up the speed required to get into planing like the real MTB on the water.
2) Relating to the above, she also did not show the bow-up running even at "higher speed" judging from/despite of the powerful sound in the midst of the video.
3)I could not confirm if the boat was water-cooled adequately that were quite indispensable to get her to run continuously fast.
  A brushless motor for use of fast boat had best water-cooled for running over several minutes. 
Above mentioned impressions are just my straight and superficial, but the investigation of the cause/background of them are worth doing deeply based upon the indications already stated as the above by other people.
Wishing you a wonderful video of the second trial run.
   
Pics below are typical sailing scenes of MTB Elco 80 type for your reference.
a) Actual boat PT-117
b) Model PT-109 of mine
and the video in the planing mode, fast but calm with normal brushed motors.
Lindberg 1/32 PT109 sailing test resulted in success in the third trial run. (youtube.com)

[DougMRC]

 Hi All
Update on replies to my post so far.
The 109 was originally built in 2012 by myself and has been modified / upgraded several times since then, unfortunately, I am not a perfectionist when it comes to exact detail to all my models, I’m not into plastic sailors, guns and turning radar scanners unless they actually work, which of course they can’t, although, I think I may like to have working guns (well maybe not) I mainly concentrate on the build quality and the highest Tech that I can afford to fit in them; I have 6 models with only 2 having a close true copy to the original ships. See photo of RMAS Grasmere A402 my 2^nd full time command of the early 80s and the white super yacht. 
To answer some of the very relevant and accurate points given in the reply posts so far (thank you and much appreciated)
The posted video of model No. 1  PT109 was the first run and tweaks were later made to the stern trim tabs (I know ELCO's did not fit trim tabs but I like upgrading) these were set too low and pushed the bow down at speed which explains the lack of planning and the overly large bow wash. For the 2nd run they were adjusted up slightly and the two 11.2v lipo batteries in the bow section were them moved astern of amidships, she ran a lot smoother and made the plane comfortably but still has an nice bow wash, (unfortunately my wife appears several times in that video and she has forbidden me to let it be shown – So Sad, I told her not to walk in front of the base station camera, haven’t a clue as to why she’s normally very camera shy.
Due to my full time work and the building of 7 other modes and a camping trailer, 5 boats and two high powered, fan cooled, twin motor 4 wheeled drive cars, therefore, I didn’t have the time to take the boats out on the water for a third run (luckily I have a two meter boat testing tank/trough for ballasting and engine trials in the back yard), but having recently retired, “it’s now playtime”.
PT109. The weight without the batteries is 16KG, with batteries (4 in total including a 12v NP7 for ancillaries) gives her a DW of 19.75KG so quite heavy. Her hull is made from a resin coated (in and out) ¼” marine ply which makes her that much heavier than normal painted ply.
Her speed on the 2^nd run according to the fitted satnav system was recorded as 22.5 mph, she will go faster as I use computer programmable transmitters and the throttle is set at 85%, I also agree she’s much faster than scale speed and the propellers are wrong for the original but I’ve gone with tech and more power than needed. (Just for FUN)
The ESC’s are water cooled by a 12v pond pump which works very well and as for the motors there is a high capacity cooling fan installed and with her running a full speed in my tank for 20 minutes all three  motors remain just warm to the touch, so no problems there. This was done in reverse as  in forward mode she tends to dump most of the water out of the back of the  trough as she’s a bit long for it?? (Dirty girl). I will post some still photos and tech notes of the PT109 to later.
Just a note to one of the replies; having the three large brushless motors and up to  210amps to run them, eases the strain on each so they run smoother and faster as they are not under an individual unit strain to push such a heavy boat. (Just think of it as one or three people pushing a car). (More photos and info to follow)
I have attached some photos of the other models that I have built. (for info, as far as I know, Grasmere A402 was one of two MOD Clovelly-class fleet tenders that had an original fit foremast, which was eventually removed “after my time on her”. the other was Criccieth A391 My 1^st full command but the mast was broken under the bow of a large ship whilst my crew was trying to remove an unwanted pickup from her fouled anchor. It was wooden (who would put a wooden mast on a metal ship??) it only had a little crack in it. I suggested Gaffer tape!! but they said it had to be removed for safety, oops! my fault, so no Bravo Zulu for us even though we successfully got the job done, See photo – that’s me in 1980 wearing the light jumper on Criccieth’s fore deck _ I’ve aged a lot since then.
Other models:
No. 2 Grasmere, (More photos and info to follow)
No. 3 PT101 (TUG) far too much tech on this one. (More photos and info to follow)
No. 4. PT102 (Fast MTB). (More photos and info to follow)
 No. 5. A Plastic super yacht my 1^st model (no name, as I don’t like it that much) (More photos and info to follow)
No. 6. An SSRV. She is a Shallow Sea Recovery Vessel) - as opposed to a “Deep” SRV. She has a working camera drone along with 5 other cameras all viewable on the base station due to the onboard telemetry unit, she has a casualty recovery depth of 3 Meters, but if you want tech this one has it in spade loads. (More photos and info to follow)
No.7. is a reconfigured (and now high powered) HOT BODDIES car. Which in my original direct drive configuration out accelerated my then neighbours Subaru Impreza WRX, (More photos and info to follow) and finally. N0. 8.  SCARAB (remote controlled) originally built as a caravan mover to get our camping/model boat trailer in and out of the garage, but continued to work on it to what it is now (very large and really weird looking. you wouldn’t want to run into it on a dark night) – weighing about 35KG with two 24v motors on front and rear differential drives it has plenty of power and can do most things a car can do but at up to 1500 metres away from the driver.  (More photos and info to follow)
As I said,” I go with the best tech I can get and the build quality”,
All models with photos/videos and specs will be posted in due course, some may like my style of model building, others may not,

[DougMRC]

 Hi All
The photos did not appear on the forum for some reason but you can see them on my YouTube channel https://youtu.be/_lpwXh3GXWs this is an invitation only post, not everyone can see it. Sorry for the Wondershare watermark but its not easy to put individual photos on YouTube, you have to convert them to a video first and the easiest way I can do it is through Wondershare’s excellent program, enjoy and please let me know your thoughts “good or bad” if it works OK I will make a subscription to Wondershare which will remove the watermark in future photo posts.

[Backerther]

Hi


I suppose that you could edit the video in order to eliminate what you (she?)would not wish to let us show ...???
The video /motion pictures is the best to represent the moving RC models despite of their kinds than any other still images....
"Seeing is believing" might be common and universal in all ages and countries...??
Good luck with your gigantic size model of PT-109.!!