robotronski

So when I saw a post here about a Mustang I read it hoping it was about a heavily modified SIG Mustang 450 Pylon racer I recall seeing way back when (1987-1990)

There was a guy who would come to the same Fly-in every year with this wickedly fast plane.

He used the SIG kit as a start but hacked it pretty good to the point it did not look like the original model at all.

After seeing this same plane for a few years I fianlly struck up a conversation with the guy to pick his brain about how he got so much speed.

So heres what he did:

1. He removed the undercamber from the wing tips and I recall the airfoil was razor thin at the tips. Wing was sheeted with balsa and had carbon fiber reinforced stringer to help with G-loads in turns. Wing was heavily modified with reduced wingspan as well.

2. Only one side of the wing had an aileron the other side was clean. (dont remember which side it was L or R) Was barn door type not a strip aileron. The thing still had an very fast roll rate too with ony one tiny aileron.

3. No canopy as an unmuffled tuned pipe sat where the turtle deck normally goes

4. No wheels but he had landing gear. Gear was 1/8 to 5/32 music wire bent into a sorta-skid configuration. Tail dragger set up with gear way forward of LE of wing. To see that thing scape around on metal for take off and landing was the best part of the show for me. Landings were always deadstck too.

5. Engine was a WEBRA 40 (speed 40 maybe) rear exhaust w/ flat slide carb, but the guy never really used any other speed other than WFO.

6. Prop was a modified wood that only had a 9" diameter. I can only imagine what the pirch was... Helped out with drag and allowed for the stubby wire landing gear too.

7. Had like a 4oz tank as he'd only fly a very short time then scraper her on in... I know my nerves would be shot after 2-3 minutes at that speed. Plane got tiny REAL FAST !!!

Flights were hard to watch too. Guy always did left to right passes down the runway at about 10' altitude. As soon as he'd pass field center, he'd pull up into a loop and roll out w/ an immelman then dive in again for another pass.

Never saw a RADAR gun on the plane but I've been to many a Grand Prix/SUperbike race and those bikes do 160mph to 185mph and this guy was about the same apparent speed. Not really sure how fast to be honest.

I even have a good color photo (somewhere) I took that I need to scan and upload for all to enjoy.

Oh, and after I talked to him the last time, I placed an order with SIG and got me a set of Mustang 450 foam cores. Still dreaming about building my own speed demon myself I guess.

Kmot

My Feedback: (24)

Sounds delicious! Hope you can get the pics uploaded. [8D]

robotronski

Oh yeah, and now I recall the builders name.

We all called him "Fast AL", go figure...

Moddest guy too, not one to brag about his speed

rcflyer1970

My Feedback: (212)

I had a couple Sig 450s, top left in pic (old pic 1987) was my first one, OS VRP 40 with a OPS 60 Marine Carb, 40% nitro, pipe set for 26k, it had to be put in a dive to get on the pipe but once on the pipe you had to think quick. Had a wing tip flutter and after 20 flights the rt. wing tip blew off in a dive. I had glassed the wing out to the last 4 inches that's where it departed (thin wing tips). I had thought all along it was aileron flutter that I could never seem to get rid of. I had a clipped wing Little Toni with a Terry Prather Custom X-40 that ripped up the sky before it blew apart in a screaming dive (cause unknown) it just blowed up.

combatpigg

My Feedback: (3)

For it's day, I'm sure it was wickedly fast, but if you want to see fast now, check the schedule for Q-40 pylon events in your area and check it out this summer. It's awesome.

robotronski

So today I'm digging around and I found the picture of the Modded Mustang 450 speed machine.

I bet I havent seen that photo in over 7 years !!!!

Its an excellent photo as you can see all the neat stuff this plane has including the music wire landing skids.

I don't recall being that good a photographer either...

Will try to scan the photo in and upload it here ASAP.

Robo

bob27s

My Feedback: (19)

the Sig 450 was essentially an early 1970s F-1 design.

Yes, designed for quick. Not sure if it would be capable of much over 160 with a Webra 40 speed and pipe combo. Possibly.

As noted, if you have the opportunity to go to a QM40 race..... bring a chair, some sunglasses, and enjoy

jaka

Hi!
SIG Mustang was a seventies design and by todays standard not particularly fast. Todays F3D or Formula .40 pylon airplanes can tripple that speed.

LGM Graphix

My Feedback: (22)

Triple? Not even close :P even if it only did 80mph in the seventies, that would mean that a Q40 or FAI bird would have to do 240mph. Possibly out of a good dive, but the old Sig Mustang can easily break 100mph, probably hit 150mph without tooooooooo much trouble, that means you'd have to be going 450mph to triple the speed, not happening, not even with a turbine jet......

robotronski

Yes, you are correct, the SIG 450 kit was in fact a late 70's design, but this guy's plane was a bit modified to say the least. However you know nothing about his engine tuning or prop selection either. Is it possible he may have done some internal porting to the cylinder sleeve, we don't know do we, but there are several pilots around back then and today who are quite capable of producing a .40 glow motor that will make extreme power for a very short duration. Remember, he only flew for about 3 minutes as I stated earlier. What fuel was he using? You don't know that either. I will say this , that same year I saw Bob Violet (and his daughter who also flew, a rare known fact) fly BVM Agreesors at speed at the same field and they werent nowhere near the speed of that 450. Even at a very conservative top speed of 100 mph for that 70's modded 450 would require an approximate top speed of a formula .40 pylon racer to reach over 300 mph in order to reach that speed by a factor of 3. All of this on glow fuel as well. Sorry, but I can't agree with that statement. Look, I'm not saying this is the fastest prop plane ever flown, but I will say it definently was not 3 times slower than the prop stuff out there racing today. Thats all.

robotronski

Well, they say a picture is worth 1000 words...

[img][/img]

HighPlains

My Feedback: (1)

I can tell you for certain that it takes a much higher fuel burn to achieve 160 to 185 mph with a Formula One model of any vintage.
Small model looks as fast as bigger motorcycle while going slower. That engine and fuel burn would place it around 140.

combatpigg

My Feedback: (3)

Cool looking plane! Those gear legs look like they would just dig in and slam the nose into the ground, but I've never seen anybody try it before. The sense of speed is relative to your surroundings, too. I've flown fairly fast planes at small fields with nearby trees and they looked very fast, but at a large facility or area they don't seem as fast.

rcflyer1970

My Feedback: (212)

I know I flew my M450 in a very large area and it covered ground very fast, mine was only set up for dive speed so it was hard to get on the pipe since it had to be set burbuling rich and wouldn't get on the pipe until in a steep dive, once on the pipe it would stay there till it died. I don't know about tuning the Webra engines but the VRP 40 responded well to minor port cleanup and it liked OPS 29 marine pipes with a small stinger set at about 8.5 inches for hi rpm but was allways a glow plug eater. It was capable of serious rpm in flight but only good for about 3 passes and it sucked a tank of fuel. I fly at Speedworld there are race planes flying everyday and while the old planes will in no way compete on the course they could still be setup for respectable all out speed since that doen't require tight turns or large wings.

Ed Smith

Well, having now seen the picture, interesting and fast no doubt, but hardly a Sig Mustang 450!

Ed S

Ed Smith

Double post deleted

bob27s

My Feedback: (19)

Ok... its speaks ! Thanks for posting the photo.

Here is what I see in the photo:

That is an OS 40VF or 45VF engine - nitro pipe (kinda fat, maybe marine setup) looks like it is set around 9-10"
Prop appears to be a standard blade RevUp 9" - appears stock - likely a 9x6 or 9x7.
If this was set up right, and perhaps with some nitro, the engine would be turning around 17,000 - perhaps a bit more in the air.

Those wire stubs might actually create more drag than the standard 450 landing gear. Round wire is a bad thing.

Anyway...... all things considered, this may be a 140mph aircraft. Maybe 160mph from a steep dive on a good day.

The important thing here Robotronski, is that you appear interested in quick model aircraft. And the good news here is that if you enjoyed watching this particular aircraft really move out.... building a sport-speed aircraft today, capable of that same performance, is relatively easy (this is what Jaka was getting at in a general fashion).

mmattockx

If you are looking for a simple, easy way to get speed a Q500 and hot 45 will get you going 120mph easily and a Jett 40-60 will get you over 150mph with little trouble. I had a thread a while ago about getting to 150mph as simply and easily as possible and this is the way to go:

http://www.rcuniverse.com/forum/m_54...tm.htm#5422611


Mark