Hip Pocket Builders' Forum

Control Line Forum => Sport => Topic started by: Viking61 on November 11, 2011, 07:07:23 PM



Title: Dick Sarpolus P-51 1/2A profile
Post by: Viking61 on November 11, 2011, 07:07:23 PM
Hi, I'm new to the group and this is my first post.  I was wondering if any of the members of the forum have had any experience with the Sarpolus P-51 profile in the plans section.  I have a BigMig .061 and I'm wanting to use on a plane for my grandson.  This sure seems like a big plane for that size engine, and I am wondering if the .061 will pull the plane adequately and do basic maneuvers.  Any assistance or recommendations will be appreciated.


Title: Re: Dick Sarpolus P-51 1/2A profile
Post by: Sundance12 on November 11, 2011, 08:03:32 PM
Yup, beyond your expectations. The .061 Big Mig is almost too much, and don't be afraid of that model's size, it will be a good one for that motor.

Bruce F.


Title: Re: Dick Sarpolus P-51 1/2A profile
Post by: Glenn (gravitywell) Reach on November 13, 2011, 03:37:34 AM
I built one ten years ago and powered it with an .049TD.  It did the entire pattern!  Anything by Dick is worth building and having fun with.  Go for it! ;D


Title: Re: Dick Sarpolus P-51 1/2A profile
Post by: Viking61 on November 14, 2011, 03:32:40 PM
Thanks for the feedback.  I am going to build the P-51.  I have made poster board templates and cut out the plywood engine mount sides to make it easier for my grandson to help build it.  Next, I'm going to build a fuel tank for it.  I'm debating between uni-flow and pressure.  If I use uni-flow venting he can always fly it without the muffler if need be.  Again, thanks for the replies.  Any other suggestions are appreciated.


Title: Re: Dick Sarpolus P-51 1/2A profile
Post by: Aviatortroy on March 06, 2016, 11:50:53 PM
Hello guys, I know this thread is 5 years old but I wanted to comment in case anyone else is building this model.  I recently printed out the plans and immediately thought wow, that looks huge! I researched the span and wing area of several popular 1/2a models including the ever popular Sig Skyray, and decided to reduce the plans to 65% which gives about a 20inch span and 71 sq inches. I hope I didn't go too small as all the wood is cut already! I'm planning on using a plain Jane Cox baby bee which I'm sure has way less power than the Norvel .061. Wish me luck...haven't flow control line for 30 years.


Title: Re: Dick Sarpolus P-51 1/2A profile
Post by: Viking61 on March 07, 2016, 09:23:00 AM
I have one that my grandson flies.  It has a BigMig 61 running with muffler pressure and flies well on 35' lines.  It is both fun to build and fly, and looks great when finished.


Title: Re: Dick Sarpolus P-51 1/2A profile
Post by: NEW222 on March 07, 2016, 11:48:51 PM
Hello guys, I know this thread is 5 years old but I wanted to comment in case anyone else is building this model.  I recently printed out the plans and immediately thought wow, that looks huge! I researched the span and wing area of several popular 1/2a models including the ever popular Sig Skyray, and decided to reduce the plans to 65% which gives about a 20inch span and 71 sq inches. I hope I didn't go too small as all the wood is cut already! I'm planning on using a plain Jane Cox baby bee which I'm sure has way less power than the Norvel .061. Wish me luck...haven't flow control line for 30 years.

18-20 inch should be good. Just remember to keep it light as possible.


Title: Re: Dick Sarpolus P-51 1/2A profile
Post by: Aviatortroy on March 08, 2016, 11:58:30 AM
Well I chickened out and re sized for 80%, this came out to 23.5 inch span which is exactly the same as the Skyray and others. Almost done, now I have to pick a paint scheme.

I can't wait to give it to my son, at 3 he's a little young yet for scratch building but I'm sure he can take some dual instruction on the handle!  ;)


Title: Re: Dick Sarpolus P-51 1/2A profile
Post by: Bob Jablonski on March 18, 2016, 07:36:17 PM
Incase you are interested Black Hawk models make this as a kit. Full hardware kit included.
Mr. Bob
Countyline Hobbies
Grovertown, IN.
574-540-1123
[email protected]
www.countylinehobbies.com


Title: Re: Dick Sarpolus P-51 1/2A profile
Post by: LOUCRANE on July 01, 2016, 02:53:29 AM
Another thing sport fliers might benefit from checking out... particularly for smaller engine models.

The new fishing line material available, e.g., brand name Spiderwire and similar (several brands available) is amazing stuff! FAR thinner than Dacron or monofil (less line drag) and much less stretchy. Lighter. Less fussy to live with than single strand metal 0.008" lines.  Not cheap on first view (prices for metal lines are even worse!) but spools will make many sets of 40'-50' lines. Several "pull test" ratings available. 15 to 20 lb probably more than covers metric 1/2A (up to .061 cu in  modern engines) needs.

CAUTIONS: New techniques for handling, and forming line ends require awareness, practice and effort.
**Proven and safe useful knots are illustrated on at least the Spiderwire packaging.
**DO NOT try to break this line by wrapping it around a finger and pulling - unless you really mean to remove that fingertip!
**Similarly, do not 'roll in' the line under firm tension on a plastic reel. (Crushing force apparently is additive, so 2 lines taking 30 turns at 15 pounds could mean 900 pounds crushing force!) (Haven't tested this; don't care to...)
** The lines are a bit hard to tie off to equal lengths (complicated knot procedures, particularly for the most highly recommended double uni-knot.) Some means of line length adjustment to give a 'comfortable neutral' handle position is necessary.

AMA Competition rules acknowledge this kind of flying line for limited purposes; check the control line section of the rulebook, which is free to access at:
http://www.modelaircraft.org/