Namba April Propwash

[LohringMiller]

For those of you reading my article on high speed boat design, there is an error in the print version. The picture of Mike Bontoft's rigger and sport hydro with spoilers is swapped in the print version. The web version is correct. In any case, the web version is better with high resolution color pictures.

Lohring Miller

 

[RaceMechaniX]

Lohring what ever happened to Mikes 1/4 scale electric hydro? Did he ever run it?

 

[Kevin Sheren]

http://www.namba.com/content/library/propwash/2017/april/files/assets/basic-html/index.html#1

 

[LohringMiller]

The electric model was 1/4 the size of a full size lead acid powered electric boat we were designing to attack the 50 mph world electric record. The electric model was overpowered compared to the full size boat and actually went 93 mph on 40 cells. We ran smaller props and did a series of tests to look at take off. The wings were to get the heavy boat out of the water. Mike actually started construction when I discovered that any commercially available battery was allowed. Mike sold off the 12 lead acid batteries and had a bonfire with the boat parts. He went on to build a conventional outboard hydro with 42 - 6S Enerland lithium polymer batteries and the rest is history.

http://www.intlwaters.com/index.php?app=gallery&album=542



Lohring Miller

 

[LohringMiller]

I also noticed that the picture illustrating a full size blow off was omitted. It doesn't contribute to the article, but its a spectacular example of wing in ground effect problems.

Lohring Miller

 

[Al Waters]

I really do apologize Lohring. I upgraded MS Publisher to a newer version and it has this little trick where when I go from the printed version black and white pictures to replace with color version pictures, it is supposed to do them all at once with one click. I will fix this. I have a feeling that the printed version Propwash out for mailing will be correct.

Thanks,

Al Waters

 

[Christian Holmstedt]

Edited out. It was OT.