Expert: Ken Myers - 10/21/2009

Question
House of Balsa 1/12 scale list eng. required as TD .051-.10
What does the ,051-.10 refer to?
I think the TD refers to Cox engs. which are not made any more.
Are there any glow engs. that that are still made that would be
suitable for these kits?
  For instance a Thunder Tiger GP-07-TTR 9007.
If you know of any glow engins that are still manufactured
that would work in 1/12 scale air planes could you list some?

Answer
Hi James,

The .051 - .10 refer to the displacement.  You are correct that TD refers to the no longer produced Cox Brand engines. TD was their trademark Thimble Drome.

The engine you noted, if it is a .07 size would work.  I had one of these HOB P-51s with a TD .051 and it was a great flier "back in the day."

I found this engine, that you might want to consider

http://www.hobbypeople.net/gallery/211280.asp

It is a .061 and weighs 1.9 oz. with the muffler.  It should work.

If this is the Thunder Tiger you were talking about

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXRWT3&P=ML

it weighs almost twice as much, according to the specifications.

You really want as light a motor as you can get.  I see the Hobby People motor is more money, so you need to make your own choice.  

Swap shop season is coming up.  You might want to check to see if local clubs are having swap shops and you might be able to pick up a Cox motor, but only do that if you can also get what appear to be new glow plugs for it.  You can check for local Academy of Model Aeronautics clubs at http://www.modelaircraft.org

Hope this points you in the right direction.

Happy and successful flying,
Ken