While the world only needs one Perky Postal Contest Black Hawk Models would like to sponsor an American Perky Postal Contest. While I, as most of you already know, an against rules there need to be a few for safety. Start date 1 January 2008, End date .. July 4, 2008.
Trophies for:
(No trophies or awards for the highest speeds.)
Ignition engine
Diesel engine
Glow engine

Engine size
Glow .14 to .1525
Diesel .14 to .1525
Ignition .19 to .23

Control lines, plus leadouts, .015. (or larger) Two line control system only.
Line length from center of handle to center of plane 52' 6".

Suction feed only.
No tuned pipes or performance enhanced exhaust systems.

Model built to plan outline.
Builder must fly and submit times.
Two wheels of at least 1 1/2" dia.
Reccomended but not enforced as a rule: Bellcrank mounted to/attached to motor mounts.
Recommended fuel 10% nitro or less

16 laps (one mile) timed.
3 entries per contestant allowed.
Winner is the closest to the average time, in case of tie best time under average time wins.
No entry accepted with speeds over 90 mph.

Since Black Hawk Models will not be present for any building or flying of any models competing in this or any other event we reccomend that ALL safety measures be enforce at ALL times. We recommend that ALL equipment and ALL aircraft be examined carefully before each flight and that if there is anything that might, in any way malfunction, break or cause the model to perform in an unsafe manner that and any future flights with this model and/or equipment be terminated until satisfactory repairs and/or replacements can be made. Black Hawk Models does not accept any liability for any injuries or damage caused by any model aircraft, or equipment that may be used injunction with any model aircraft, in this event or any other event. We do recommend that ALL equipment used be approved by the AMA and sanctioned by them for the use that it is intended for. We also recommend that ALL model aircraft be tested by the AMA standards and in conjunction with ALL AMA rules and guidelines this is to include, but not limited to, a pull test and the use of a control handle thong to secure the handle to the pilot.

All entries must contain:
Name
address
Type and name of engine used
date of flight
flight time/speed
optional photo

           I am flexable on the line size but I would like to hear from more people on this before I make any changes. I do not understand how a different line size would handicap you in a postal event. I am also hesitant to change it because that might limit those who compete in other Perky events from competing in ours.
Larry 

I don't disagree with anything Paul has said here.  I think that the disconnect is that no one would have envisioned a Perky with an open face Nelson 15 in it--or a current Fora or hopped up CS, etc.

Larry:  I would contact Bill Hughes or one of the NASS guys about the structural requirements for these planes.  If they start going much over 80-90 MPH, they might need to go to .015's like Paul said.

This can be discouraged from the start by NOT offering prizes for the fastest times--just the averages like the postal events.  The other thing that could be considered is to not allow posting of break-uot flights  ie over xx MPH. 

The Perky is a VINTAGE design--it was set-up for ignition engines for crying out loud.

Flying one flat-out with a current .15 is probably not safe--unless the pull testing can ease the concern.

Lets make sure it doesn't start requireing cutoffs, mag pans, pipes etc.

Lager lines are a good way to control the top end and it is well recognized method in the speed community.

But again, I would contact the NASS for recommendations.

FWIW

Curt

One of the fellows that ordered a Perky kit is a NASS member I've asked him for a link to NASS. Also asked for rules. I should be able to have info.
I for one would like to stick to NASS rules.
I do like the idea of a Black Hawk sponsored Perky postal race. And January to July of '08 sounds like a good start.
We still have about 3 weeks before the Perkys end up in peoples hands and then at least a couple weeks before they get flown. That'll give plenty of time to get the rules.

In any event, safety rules need to be set to the WORST CASE, not the expected average. 

In addition to Nelsons, there  are plenty of OPS, Rossi, and eastern bloc engines with names most of us don't know.   Suffice to say, 108 MPH is the highest speed claimed to date, and it will be broken on .012' lines for sure.  Probably on bigger lines as well.

These planes won't go as fast as an F2a or an AMA Class A, but they're not just a big ZigZag with a Black Widow.

Paul and all,

First,  the Perky Class will become dominated by all-out speed, for bragging rights, if nothing else.  (I flew a Cox Olympic Perky in the first Postal Contest and know that my next one will target 110MPH)  Safety is always an issue, and line characteristics should conform to AMA standards for CL Speed, based on a reasonable estimate of actual speed (timed average or true peak speed?), revised upward as speeds increase.

Stranded cable has got to go, replaced by ASTM music wire.  0.012 music wire just barely conforms with AMA requirements assuming a 24 Oz airplane and 110 MPH.  AMA calculated G on 52.5 ft lines is 20.3 G; times 1.10 (from AMA) is 22.33G.  Using AMA breaking strength data, 33.72 pounds is the maximum pull permitted for 0.012 lines, which is 1.51 pounds for the airplane.(which confirms the 24 ounce maximum airplane weight.  If pull test is rounded up to say 24G, maximum airplane weight drops to 22.5 ounces.

More tomorrow.

Will Stewart

The reason for the safety rule about attaching the bellcrank to the motor mounts:
           The 2 things that seem the most dangerous to me is 1- the lines break and allow the plane to hurl out of control into the spectators and 2- the plane breaks up and allows the engine to fly into the spectators. .015 lines should cure the first problem and even by 1946 speed fliers knew to attach the bellcrank to the motor mounts so that even if the plane came apart the motor would stay on the lines.
Larry

ALL,

Continuing from last night.  First, did not mean to confuse anyone about airplane weight, the 24 Oz was a maximum model weight ala AMA calculations, as noted in the last sentence.

As for stranded lines, unless the latest AMA rules have changed it, the only racing event allowing multi strand lines is 1/2A mouse racing.  I see Combat uses stranded 0.015 so they are available.  The real safety issue is, as Bill Hughes says, not how the bellcrank is attached, but insuring that the airplane, lines and handle pass a reasonable pull test prior to flight.  I don't have any breaking strength information on stranded wire but note that AMA calls for a standard 25 pound pull test on 0.015 multi-strand in .15 Combat (This may have changed in latest rules), based on 60 foot lines and a four pound maximum aiplane weight.  (For the numbers to work in this class, a four pound airplane would only be pulled 6.25G, which is scary)  If AMA considers 0.015 multi-strand only good up to 25 pounds pull test and max Perky weight is 24 oz, this works out to only 16.7G (20G for a 20 oz airplane), way under AMA calculations.

Next step is for the advocates of multi-strand to provide breaking strength data similar to what is available from AMA for solid ASTM wires.

Will Stewart

Larry,

Reading the rules as presented in the first post, I'd strongly suggest adding "or larger diameter" after ".015" in your rules to cover the litigation averse, and add a reasonable preflight pull test for the same reason.  Trying to stay within AMA insurance coverage.

Will Stewart

We have several decades of data from F2d that proves that .015" stranded lines are perfectly OK for this sort of application.

In the "golden age" when we could use big venturis, pressure systems, and all the nitro you could afford, the best could do was 120 MPH.  That was with 350 square inches of wing area and no wheels.

I consider the wing area vs landing gear something of a wash.  The target-weight of a Perky and an old F2d was the same, about 16 ounces.

Compared to the "old FAI", Perkys are already speed-limited by SUCTION FUEL SYSTEMS, which forces a small venturi.  I think a nitro limit would be a needless constraint and also a fatal rule for the owners of exisitng engines designed to use nitro. 

Larry;

Ignore the latrine lawyers.  I'll bet none will build or post an entry in the postal contest.  I've built 3 so far using different engines.  Mine have been in the 65 to 75 mph range.


Tom Wilk 

Hi Tom,

Missed your name on Bob Langelius' Perky Postal summary.  My official time was listed as a woeful 70.29 with a Cox Olympic .15. 

While I'm not an attorney, latrine or otherwise, I have testified  under oath in a deposition, involving a Dynajet ship into the crowd at an airshow held at Mercer County airport, Trenton N.J, in Sept 1959.  Even tho the plaintiff's lawyer was a dim bulb and the suit of the lady, whose arm was brushed by model shrapnel, was dropped,  I'd like to spare you the experience since it was no fun.  (My ship, MagnaModel Jet-someone else's engine and the pilot's lines which broke at the handle). 

Do as you see fit, but my flights will be preceeded by a witnessed pull test.

Cheers,   Will Stewart

OK GUYS THIS IS AS CLOSE AS I HAVE COME TO ZAPPING A POST. I BELIEVE STRONGLY IN FREEDOM OF SPEACH BUT THAT CAN BE DONE WITH OUT ANY NAME CALLING . PLEASE KEEP IT CIVIL . JOEY A.M.A.#9806, N.A.S.S.#88

I've never paid much attention to events other than stunt although I've watched them all at one time or another.
Based on what I've read here the Perky if flown and powered according to the rules won't pose much of a threat in the hands of most pilots.
It appears that the Perky is an entry level speed model....That's me.