stunthanger.com
General control line discussion => Open Forum => Topic started by: bob whitney on July 23, 2015, 12:03:18 PM
-
where can i find rules for profile stunt fuse width and can the engine be inverted??
-
Hi, Bob. As far as I can tell, there are no "Official" rules for profile stunt, at least from the AMA. The AMA has a definition of a "profile" airplane but nothing specific to stunt.
There are some regional rules such as the NW region : http://flyinglines.org/rules.profilestunt.html
-
Hi, Bob. As far as I can tell, there are no "Official" rules for profile stunt, at least from the AMA. The AMA has a definition of a "profile" airplane but nothing specific to stunt.
There are some regional rules such as the NW region : http://flyinglines.org/rules.profilestunt.html
+1. If someone's putting on a profile event in your area, you need to ask them to tell you the rules. Unless you want to come to Oregon and have fun with us, in which case the rules that Bill linked to are what you need.
If someone isn't putting on a profile event and you want a simple plane to build, look at a Neibur (sp?) Hobo. It combines the ease of construction of a profile with the rigidity of a full fuse.
-
Bob, check in with a PAMPA guru and see what they say.
Wayne
-
thanks guys ,pretty much what i found also. i like the N/W rules, this ship will proply be flown at Brodaks so will check with Will and see what he has to say and that would probly cover Huntersville also
-
Hi Ty,
I am not sure either why they're using the 1/2" rule but here's what I found
CLG-09-2 – This proposal clarifies the definition of profile model in CL competition events.
Class/Event
Max Width
including
Plywood Doublers
Max Cheek
Cowl Width
1/2 A Proto
1/2 inch
3/8 inch
Scale Racing
5/8 inch
Slow Combat
3/4 inch
3/4 inch
Carrier
3/4 inch
3/4 inch
Slow Rat Racing
and Rat Racing
3/4 inch
To: 10. Profile Definition. The fuselage of a profile model resembles that of a conventional airplane
in the side (profile) view and appears as a thin flat sheet in the plan (top) view. When a conventional,
single cylinder, internal combustion engine is used, the engine shall be completely exposed from the
centerline of the crankshaft to the top of the cylinder head when viewed perpendicular to both the
crankshaft centerline and the cylinder centerline. In the case of internal combustion engine with
multiple cylinders, the preceding rule shall apply to all cylinders with allowances made by the officials
for appropriate mounting of the engine. No fairing may be added to the engine which violates the “completely
exposed” requirement of the previous sentences, and the engine cylinder shall not be contoured to present a
streamlined cross section to the airflow. Additional reinforcements such as plywood nose doublers and cheek
cowls or fairings are permitted within the width limits defined in the accompanying table. Such additional
fuselage reinforcements may extend from the prop drive washer to a point 25 percent of the wing root chord
back of the wing leading edge at the root and may be faired in. Cheek cowls used in Racing events may be of
unlimited width, but may be used only on the side opposite the engine and only on models with side-mounted
engines. Engine mounts may protrude from the fuselage sides beyond the width limitations of the table.
They may extend no further aft than 25 percent of the wing root chord back of the leading edge at the root.
Any such protruding engine mounts shall be of constant cross sectional shape and dimensions, without tapering.
The rear portion of those mounts shall terminate in an angle of at least 45 degrees to the longitudinal axis of
the fuselage unless they terminate within the wing structure. Nacelles, as used on multi-engine models are subject
to the requirements of this definition.
Profile Fuselage Width
Class/Event
Maximum Fuselage Width
Max Width of Additional Reinforcements
1/2 Proto 1/2 inch 3/8 inch
Scale Racing 5/8 inch No limit
Slow Combat 3/4 inch 3/4 inch
Navy Carrier 3/4 inch 3/4 inch
Slow Rat Racing and Rat Racing 3/4 inch No limit
Logic:
There are ambiguities in the present rules, and the present rules provide no guidance for radial engine mounting
or any engine mounting configuration other than horizontal (side) mounting using lugs on the sides of the engine
aligned with the crankshaft. The increasing use of electric motors adds additional questions on how to accommodate
the common radial mounts of these motors which are generally wider than the reinforcements allowed in the present
rules. Electric motors are cylindrical, but have no “cylinders” as implied in the rules. The protruding engine mounts
portion of the rule is ill defined as to what constitutes “faired in”. The same poor definition applies to the requirement
that the engine “not have any type of fairing”. Wings and fuel tanks constitute “fairings” in that they can reduce the
drag of an engine cylinder, but common practice has allowed such installations as not violating the fairing rule.
“Plywood doublers” mentioned in the table are nothing more than reinforcements and should be treated as such if they
exceed the maximum fuselage width since neither the material (plywood), the configuration (doubler) nor the dimensions
can be determined in most finished models. The reinforcements specification for other than side mounted internal
combustion engines is subject to interpretation, but is almost universally allowed. Only fuselages are discussed in the
current rule, but nacelles are relevant in multi-engine models. This proposal clarifies all of these issues without changing
the generally accepted (but not codified) interpretations of the existing rule.
Submitted by: Richard Perry, AMA #243
Plus I have added the AMA Competition Regulations - Control Line General Rules
on my website on the rules page which is found in the helpful hints section..
Rules page link
http://www.builtrightflyright.com/MiscHelpPgs/Rules/StuntRules.htm
Direct link to the PDF
http://www.builtrightflyright.com/MiscHelpPgs/Rules/2015-2016CLGeneral.pdf
Please do not take these as the final rules, always check with AMA and or any up and coming
contests you plan to visit for their rules on any of these or other rule questions you may have
as would have been good to know ahead of time in the case noted in Ty's post
-
Bob, truthfully I have never heard of a Profile airplane having any kind of advantage in stunt. So why the concern by somebody with a rule in an event where there should be more concern about getting somebody to participate in stunt not to mention that the whole thing is about perceived quality and consistency of maneuvers anyway.
Wayne
-
Is not the justification for the event to offer something less complex than regular CLPA?
They were on the right track when the engine size was also limited to 40.
In the absence of a maximum fuselage thickness and requirement for side mounted engines, what's left of the event?
Just another set of prizes.
-
Wayne i was not looking for an advantage as most ships fly better tha i do. but l like to know the rules when i get into something new .in racing almost every class has a diff rule on cheek cowls . and i dont want to build something where the stab twist enough in flight that u can see it.
was also wondering about inverted motors
-
Is not the justification for the event to offer something less complex than regular CLPA?
They were on the right track when the engine size was also limited to 40.
In the absence of a maximum fuselage thickness and requirement for side mounted engines, what's left of the event?
Just another set of prizes.
Who said there wasn't a maximum fuselage thickness requirement for profile? The AMA rulz just put the maximum at 3/4 inch rather than 1/2 inch. They also require that the engine be exposed, lug to plug, for easy access, but don't restrict the builder to side mounted.
-
Wayne i was not looking for an advantage as most ships fly better tha i do. but l like to know the rules when i get into something new .in racing almost every class has a diff rule on cheek cowls . and i dont want to build something where the stab twist enough in flight that u can see it.
was also wondering about inverted motors
Hi Bob,
Get hold of plans or better yet one of Mike Griffin's new kits for the Mo Best and build it. It's a very well engineered Profile that pretty much complies with profile rules just about anywhere you would fly it. The fuselage builds very light and stiff and the wing and planform are typical modern 1st class stunt numbers. They fly great with any good 40 to 46 stunt engine. My choice would be an LA46 or ST46 but would work well with a good FP40 or RO Jett 40 BSSE.
I think plans are probably available from Mike Griffin also.
Oh yeah it's a great looking design also.
My second choice would be the Brodak Profile Cardinal with some control system changes. 4 inch bellcrank and larger stiffer control horns.
Same engine reccommendations as above.
Randy Cuberly
-
Wayne i was not looking for an advantage as most ships fly better tha i do. but l like to know the rules when i get into something new .in racing almost every class has a diff rule on cheek cowls . and i dont want to build something where the stab twist enough in flight that u can see it.
was also wondering about inverted motors
I didn't say you were. I just wouldn't think that someone would or should take issue of a profiles performance as an advantage when flying the pattern is the most important. I could see it in speed, racing and carrier events not stunt.
Thanks
Wayne
-
see how much fun we can have with one simple question ,Wayne ,wasn't looking for an advantage and no problem with your responce .not many profiles will fly with a good full body ship and as stated here someplace ,it is just another class to fly for most .but a must for flyers learning the pattern . there has been more than a few good flying profiles for sure .