RSM P51 Mustang

[Chris Fretz]

Anyone have a RSM P51 Mustang semi scale 56in wingspan?  Was wondering what you thought about it for stunt? Have been pondering getting this kit.

Thanks
Chris Fretz

[Walter Hicks]

Chris nothing wrong with this however a better one  is Pat Johnston Mustang 626 which has a better wing , nearly the same design.

[Chris Fretz]

Chris nothing wrong with this however a better one  is Pat Johnston Mustang 626 which has a better wing , nearly the same design.

Thanks for the info! Is this something you can get a kit of or is it just built from plans?

Thanks
Chris Fretz

[Kevin Muckleroy]

From RSM Web ad on that P51 "SEMI-SCALE FULL STUNT! Designed by Pat Johnston & Eric Rule"

[Mike Griffin]

I am pretty sure that the Kit that Eric sells is Pat Johnston's  design..

Mike

[Walter Hicks]

The kit that RSM sell is partially a Pat Johnston design. However I know Pat prettty well and we have discussed this plane.Eric Rule did not use his
wing ribs for his kit. As stated earlier the RSM kit is ok but the Pat Johnston Mustang 626 has a better wing that the RSM kit. Yes Pat does
laser cut kits but they are short kits. Again nothing really wrong with the RSM kit but if you want better preformance use PATS wing If you are not flying super seriously at contests then the kit is fine.

[Chris Fretz]

The kit that RSM sell is partially a Pat Johnston design. However I know Pat prettty well and we have discussed this plane.Eric Rule did not use his
wing ribs for his kit. As stated earlier the RSM kit is ok but the Pat Johnston Mustang 626 has a better wing that the RSM kit. Yes Pat does
laser cut kits but they are short kits. Again nothing really wrong with the RSM kit but if you want better preformance use PATS wing If you are not flying super seriously at contests then the kit is fine.

Thanks again for the info.  I tried messaging Pat on here but no answer. What is a good way to get a hold of him?

Thanks
Chris Fretz

[Mike Palko]

Chris,

Thanks for the nice comments about my Mustang in the Philly thread. My Mustang is the Hunt design. Is there any reason you would choose not to build it? Are you looking for a kit rather than building from plans?

Mike

[FLOYD CARTER]

I have built two full-body P-51 from Eric Rule's kits.  Both fly great with OS46LA.

[Chris Fretz]

Chris,

Thanks for the nice comments about my Mustang in the Philly thread. My Mustang is the Hunt design. Is there any reason you would choose not to build it? Are you looking for a kit rather than building from plans?

Mike

Hey! I don't see you comment on here much, what a treat!  Sure thing, it is an eye catcher esp if you're a mustang fan. I've been looking around all year for a mustang to build this winter. I'd really like it to be a kit. I haven't ever built from plans,  I'd pick the wrong wood grain for sure. I'd like to put a ST60 in one.
Yours has a good realistic look too, I like the wing shape and wing tips, along with the nose and tail...well ok the whole thing!

Chris

[Mike Palko]

I understand not wanting to build from plans. A Pat Johnston short kit is a good compromise and will be a great flying airplane.

Mike

[Shug Emery]

I have one it it will do the pattern.
Shug

[George Truett]

I think they're talking about the larger one with a built up fuselage.

[Chris Fretz]

Does anyone have a picture of a Pat Johnston Mustang 626?

Thanks
Chris

[Dave Hull]

I believe I have a picture that Pat sent me. But it isn't smashed down to proper forum size. Two planes side by side in red, white and blue eagle livery. Pretty!

If anyone can confirm (or correct) my assumption that these are 626's, please chime in....

Dave

[kenneth cook]

            Dave, they're pretty darn cool looking. Amazing when you see 2 identical models. It's tough enough to build one.

[Chris Fretz]

I believe I have a picture that Pat sent me. But it isn't smashed down to proper forum size. Two planes side by side in red, white and blue eagle livery. Pretty!

If anyone can confirm (or correct) my assumption that these are 626's, please chime in....

Dave

Wow if they are 626's they are rather nice looking for sure!

Chris

[Walter Hicks]

Yes those are the Pat Johnston 626. Again if you are not a top level Advanced or an Expert flyer the RSM kit will do well. 

[Dave Hull]

Eric shows a picture of what appears to be one of these two in the "details" section for his RSM P-51. Put side by side, these may be difficult to tell apart.

I attached the summary I was working on of the different Mustang C/L'ers out there. Additions and corrections welcomed!


Dave

[FLOYD CARTER]

Here are two P-51 built from RSM kits without any modifications.

Both use OS46LA engine.

Both very successful flyers,and required almost no trimming after test flight.

[Chris Fretz]

Here are two P-51 built from RSM kits without any modifications.

Both use OS46LA engine.

Both very successful flyers,and required almost no trimming after test flight.

They look very nice, Dinger muffler.  What prop are you running?

[Skip Chernoff]

Chris is a very fine Advanced flier and would make that Mustang look great!

[Chris Fretz]

Somethings telling me to go with a higher end Pat Johnston or even give the Hunt Mustang a shot.

[TigreST]

I did some photo shots of the RSM Mustang plans some years ago.  Here they are, should anybody be interested in a look see. 

FWIW,

T.

[Chris Fretz]

Does the Johnston 626 have a dihedral? Hunt? That sounds like a pain to build let alone getting a regular wing square.

Chris

[George Truett]

According to Pat's plan listing the 626 P-51 does have dihedral.  I have not built one but Pat makes a simple wing jig that uses arrow shafts locked in place to hold the ribs.  I really expect building a straight wing will not be a problem.

[Mike Palko]

Hunt’s Mustang does not have dihedral. I don’t believe Pat’s does either but it’s been a long time since I’ve seen one. Images I found on google appear to show Pat’s with a straight wing.

Mike

[eric rule]

Pat Johnston's Mustang and the one I sell are very close which is not surprising as we did the basic design together. Pat actually did the AutoCAD drawing for the plan in the RSM version and used this plan with a couple of modifications in his version.

Pat's used a slightly different airfoil shape than I did and he determined that he wanted to lift the wing tip on his in order to bring the vertical C/G upwards. I agreed with Pat about the vertical C/G but elected to simply raise the wing in the fuselage rather than go with dihedral to accomplish the change. Both models achieved the same result using a different approach. Both fly exceptional well and present well on the ground and in the air.

In my opinion you can not go very far wrong if you choose to build either one.

[Dave Hull]

The Johnston 626 Mustang plans show one inch of dihedral per panel. Don't leave it out or it will screw up your roll trim. This plane is a true, low-wing design with the bottom of the wing pretty much tangent to the bottom of the fuselage. Other designs without dihedral are raising the wing up to the CG (to align the leadouts) and giving up a bit of scale appearance. So you have to fake your brain into believing "Mustang" with a military paint job.

Dave

PS--Good input from Eric. I see we were typing at the same time.....

[Chris Fretz]

Hunt’s Mustang does not have dihedral. I don’t believe Pat’s does either but it’s been a long time since I’ve seen one. Images I found on google appear to show Pat’s with a straight wing.

Mike

Is your wing sheeted? I don't see the ribs...

Chris

[Chris Fretz]

According to Pat's plan listing the 626 P-51 does have dihedral.  I have not built one but Pat makes a simple wing jig that uses arrow shafts locked in place to hold the ribs.  I really expect building a straight wing will not be a problem.

Ok good to know thanks for the info!

The Johnston 626 Mustang plans show one inch of dihedral per panel. Don't leave it out or it will screw up your roll trim. This plane is a true, low-wing design with the bottom of the wing pretty much tangent to the bottom of the fuselage. Other designs without dihedral are raising the wing up to the CG (to align the leadouts) and giving up a bit of scale appearance. So you have to fake your brain into believing "Mustang" with a military paint job.

Dave

PS--Good input from Eric. I see we were typing at the same time.....

Pat Johnston's Mustang and the one I sell are very close which is not surprising as we did the basic design together. Pat actually did the AutoCAD drawing for the plan in the RSM version and used this plan with a couple of modifications in his version.

Pat's used a slightly different airfoil shape than I did and he determined that he wanted to lift the wing tip on his in order to bring the vertical C/G upwards. I agreed with Pat about the vertical C/G but elected to simply raise the wing in the fuselage rather than go with dihedral to accomplish the change. Both models achieved the same result using a different approach. Both fly exceptional well and present well on the ground and in the air.

In my opinion you can not go very far wrong if you choose to build either one.

Thanks for commenting on this Eric and Dave. Very helpful!

Chris

[TigreST]

Pat Johnston's Mustang and the one I sell are very close which is not surprising as we did the basic design together. Pat actually did the AutoCAD drawing for the plan in the RSM version and used this plan with a couple of modifications in his version.

Pat's used a slightly different airfoil shape than I did and he determined that he wanted to lift the wing tip on his in order to bring the vertical C/G upwards. I agreed with Pat about the vertical C/G but elected to simply raise the wing in the fuselage rather than go with dihedral to accomplish the change. Both models achieved the same result using a different approach. Both fly exceptional well and present well on the ground and in the air.

In my opinion you can not go very far wrong if you choose to build either one.

So Eric,
If the above is fact (no doubt it is) was there a change in the RSM design/production between the time I purchased my kit (non-laser cut, Hobby Fasteners production) and what could be a newer RSM P-51D?  I had a visit to your web site and see the photo ad has changed (I think?) for the P-51D and as you state the built model photo shows the wing at/close to the thrust center-line in the fuselage, maybe?.   What causes me to wonder is you state no dihedral in your kit whereas my older production run states build with dihedral.  I think the dihedral will be cool btw.   

Just wondering is all.

[Chris Fretz]

So Eric,
If the above is fact (no doubt it is) was there a change in the RSM design/production between the time I purchased my kit (non-laser cut, Hobby Fasteners production) and what could be a newer RSM P-51D?  I had a visit to your web site and see the photo ad has changed (I think?) for the P-51D and as you state the built model photo shows the wing at/close to the thrust center-line in the fuselage, maybe?.   What causes me to wonder is you state no dihedral in your kit whereas my older production run states build with dihedral.  I think the dihedral will be cool btw.   

Just wondering is all.

The wing area is listed as 610 on the website,  yours says 635

[TigreST]

I did not notice that Chris.  Interesting, ...very interesting.

[Balsa Butcher]

This will either clarify or obfuscate the issue: The May 2007 issue of Model Aviation features Pat's Mustang, listed wingspan 48". The red white and blue Mustang pics may be of that version. The RSM version is most likely based on this model thus the smaller wing area.  Pat offers plans for different sizes his scale warbird stunters, both smaller and larger. The 626 version may be the "46" sized version of his published 40 sized Mustang. 

[Vincent Judd]

I'm obviously spending too much time building airplanes and not enough time living.  I have to get out more.  I can honestly say that in my 71 years, I never heard the word obfuscate.  Or if I did, my mind was in an obfuscated state.

They say you never stop learning, I learned the word obfuscate today.

ob·fus·cate  (ŏb′fə-skāt′, ŏb-fŭs′kāt′)
tr.v. ob·fus·cat·ed, ob·fus·cat·ing, ob·fus·cates
1. To make so confused or opaque as to be difficult to perceive or understand: "A great effort was made ... to obscure or obfuscate the truth" (Robert Conquest).
2. To render indistinct or dim; darken: The fog obfuscated the shore.


And they say you can't teach an old dog new tricks.  Ha!   

[Mike Palko]

Is your wing sheeted? I don't see the ribs...

Chris

The wing is built using the lost foam construction method with a sheeted center section and open bays.

Mike

[eric rule]

The original RSM kit was hand cut and the original wing placement was at the bottom of the fuselage. After some more discussion with Pat where we talked about the design we decided to modify the P51D to bring the vertical CG more in line. Pat liked using dihedral and went with that idea in his version (which by the way comes in a number of different sizes). Since I had just taken delivery of my first laser machine I elected to make the change by raising the wing in the fuselage. As I said previously both methods accomplished a better vertical C/G so they both work. I think that it's easier for folks to build a straight wing so went in that direction while Pat likes a more semi-scale look so he went with dihedral even though it is a bit more difficult to build the wing.

As far as the different wing area numbers I used the AutoCAD function to get the area as stated on the web site.

[Chris Fretz]

I'm obviously spending too much time building airplanes and not enough time living.  I have to get out more.  I can honestly say that in my 71 years, I never heard the word obfuscate.  Or if I did, my mind was in an obfuscated state.

They say you never stop learning, I learned the word obfuscate today.

ob·fus·cate  (ŏb′fə-skāt′, ŏb-fŭs′kāt′)
tr.v. ob·fus·cat·ed, ob·fus·cat·ing, ob·fus·cates
1. To make so confused or opaque as to be difficult to perceive or understand: "A great effort was made ... to obscure or obfuscate the truth" (Robert Conquest).
2. To render indistinct or dim; darken: The fog obfuscated the shore.


And they say you can't teach an old dog new tricks.  Ha!   

I was in total belief that it was a typo of some kind, guess the jokes on me now!

[Scott Richlen]

Chris:

Pick whichever you want, but do not worry about the dihedral.  It makes no difference in the performance of the plane.  The Pat Johnston profile P-51B as kitted for us by Tom Morris flies great!

[TigreST]

A bit more chat on PJ Mustangs: A quote from a post regarding the Pat Johnston Corsair plans and such but the Mustand is mentioned:

 




Quote

 

Thanks so much Ron, Rick and all.
The RSM Mustang is a 600+ incher for the LA46 or larger.  The airfoil is from Charles Mackey "Lark".  That was the basis for my larger 626" Mustang (June 2006, MA).  The M626 has a more scale-like fuselage and my Bearcat/Mustang airfoil.  Flies spectacularly.
The Brodak Mustang is scaled down to the 560 square inch range and is very specifically designed for the LA46.  That will produce gobs of torque for the size of plane.  The result is a totally fun and competitive plane.
Rick,  I'm gratified that you followed my suggestions on the LA46 setup and are getting a 3.5 ounce fuel consumption.  That is the idea.  An engine which will do what it does on 3.5 ounces of fuel is a bargain.
Pat Johnston
Skunk Works

end quote.

That post his here:

https://stunthanger.com/smf/open-forum/brodak-corsair/

[Chris Fretz]

Chris:

Pick whichever you want, but do not worry about the dihedral.  It makes no difference in the performance of the plane.  The Pat Johnston profile P-51B as kitted for us by Tom Morris flies great!

Very nice looking Scott. Did this kit call for a dihedral and you left it out?

[Chris Fretz]

A bit more chat on PJ Mustangs: A quote from a post regarding the Pat Johnston Corsair plans and such but the Mustand is

Quote

 

Thanks so much Ron, Rick and all.
The RSM Mustang is a 600+ incher for the LA46 or larger.  The airfoil is from Charles Mackey "Lark".  That was the basis for my larger 626" Mustang (June 2006, MA).  The M626 has a more scale-like fuselage and my Bearcat/Mustang airfoil.  Flies spectacularly.
The Brodak Mustang is scaled down to the 560 square inch range and is very specifically designed for the LA46.  That will produce gobs of torque for the size of plane.  The result is a totally fun and competitive plane.
Rick,  I'm gratified that you followed my suggestions on the LA46 setup and are getting a 3.5 ounce fuel consumption.  That is the idea.  An engine which will do what it does on 3.5 ounces of fuel is a bargain.
Pat Johnston
Skunk Works

end quote.

That post his here:

https://stunthanger.com/smf/open-forum/brodak-corsair/

Is this Pat holding the airplane?

Good thread thanks for sharing

[john e. holliday]

Yes, that is the man.

[Scott Richlen]

Did this kit call for a dihedral and you left it out?

It has dihedral.  It just isn't evident in the photo.

A little more visible here....

[Chris Fretz]

It has dihedral.  It just isn't evident in the photo.

A little more visible here....

Ohhh, I see... you ment no sweat building a dihedral.

Cool looking all 3 of them together!

[Chris Fretz]

Yes, that is the man.

Thanks Doc 👍