Free Flight: Duration
Harry Murphy 3824 Oakwood Blvd., Anderson, IN 46011
NFFS News
Free Flight Digest, the official monthly publication of the National Free Flight Society (NFFS), has a new editor: Chris Weinrich. Bob Meuser — who was Model Aviation's "Free Flight Duration" columnist for many years — also performed as editor ("Rédacteur en Chef") of the Digest for about 18 years and did an admirable job. Bob announced the change in editorship with a formal letter to the various newsletter editors and magazine columnists. We should all thank Bob for his past service to the NFFS and wish him well in future endeavors.
Chris Weinrich will henceforth accept all correspondence to the Digest at:
- Chris Weinrich, 905 West 5th Ave., Olympia, WA 98502
The NFFS also has a new Membership Chairman, Nat Comfort, who replaced Sal Fruciano as of January 1, 1990. Sal served about two years in this volunteer capacity and his efforts are much appreciated.
Nat is an enthusiastic East Coast free flighter and will be receiving new membership applications at:
- Nat Comfort, 12324 Percival St., Chester, VA 23831
Membership continues to grow — there was reportedly a 60% increase in new memberships in 1989. Annual membership is $15 ($7.50 for those under 18). If you haven't done so yet, join or renew today!
As my Irish ancestors would say, "Free Flight Go Bragh!" ("Free Flight Forever!")
On a sad note, Carl Fries, cofounder of the NFFS, passed away on December 7, 1989, at age 74. "Uncle Carl," as he was fondly called, formed the NFFS with Dick Black in the 1966/67 timeframe to promote free flight competition. When I talked with him at Lawrenceville last summer, he was ecstatic over the concept of NFFS/USOC and the response it drew. He interpreted the tremendous turnout of contestants as a positive sign for the hobby. Farewell and God bless you, "Uncle Carl."
Free Flight Nats Week — 1990
The week-long 1990 USOC/AMA Nats at Lawrenceville, IL in mid-October will include the NFFS Nostalgia Gas (NosGas) National Championships. The first two NFFS NosGas champs were staged with the Society of Antique Modelers (SAM): Bob Larsh instigated the first in 1988 at the SAM Champs in Lawrenceville, IL, and Ralph Prey carried it through at the '89 SAM Champs in Jean, NV.
The NFFS-sponsored USOC (United States Outdoor Champs) concept evolved separately and its initial competition took place in June 1989. NosGas events were included as six events during that week-long affair and drew an amazing number of entrants. Due to this success, and to consolidate NFFS activities, all parties agreed that the future home of the NFFS NosGas Champs should be under the umbrella of the annual NFFS-sponsored United States Outdoor Champs whenever possible.
For 1990, the NFFS/USOC will be married to the Free Flight portion of the 1990 AMA Nats; the scheduled mid-October gathering will serve as the major event of the year. Jim O'Reilly (USOC manager) has signed Jim Bennett of St. Louis as overall Contest Director. Official dates are October 16–20 (Tuesday through Saturday).
1990 NosGas Champs — Schedule and awards
The 1990 NosGas Champs schedule will include six events:
- 1/4 A
- 1/2 A
- A
- B
- C/D
- Ignition
By popular request, the events will be spread over five days of competition rather than crammed into the first two days as in the inaugural '89 USOC.
Awards will be presented down the roster for high-entry events as far as eighth place, and at least to third place in events that traditionally show lower participation. This awards policy will apply to Rubber, Glider, and Gas events on the AMA card as well.
NosGas rules and philosophy
The Nostalgia Gas concept was intended to utilize engines (or power equivalents) and model designs of the era to produce representative power and flight characteristics associated with the specified timeframe. It is important this philosophy not be lost as NosGas popularity grows.
The Satellite newsletter of the San Valuers club reports the club is seriously considering changing local flying rules to align more closely with NFFS NosGas rules — especially excluding the Cox Tee Dee engines from event eligibility. If adopted, this would be a giant step toward nationwide NosGas rules uniformity.
Opposition argues that replacing the Tee Dee in a current NosGas model would make that model ineffective for future AMA Gas competition. My response: that is the point. NosGas is intended to support laid-back vintage glow-powered competition in contrast to modern AMA/FAI power scrambles. The Cox Tee Dee .049 has dominated the modern AMA 1/2A class since about 1961; allowing Tee Dees (or Schnuerle engines in larger classes) in NosGas would undermine the vintage concept.
Kudos to Ralph Prey and Bob Larsh for serving as stern guardians of the NosGas rule book. They issue ongoing decisions on questionable designs and provide model construction guidelines, accompanied by official NFFS "Design and Engine Availability" lists.
The latest information (Book #3, hot off the presses as of January) is available at cost by sending $1.75 to:
- Bob Larsh, 45 South White-brown Ave., Indianapolis, IN 46241
Also under consideration is changing the NosGas Ignition event from "special" status to an "official" event. The ignition event has been around for a few seasons and is gaining participation, especially in the Midwest. While some feel vintage ignition-engine competition should fall under SAM, SAM has shown little interest in recognizing the 1942–1950 ignition-engine-powered designs; NosGas Ignition appears to fill that niche.
AMA Gas classes and participation
New rule proposals for AMA Gas classes have been scarce lately; constructive revisions are needed but viable solutions are not obvious.
Domestic competition in the AMA Power classes (A, B, C, D) presents a mixed picture geographically. In the Midwest, participation has generally fallen off in recent years at even some larger contests, leaving some trophies uncontested at area and regional meets. Conversely, once-a-year large championship competitions like the AMA FF Nats (1988) and USOC (1989) drew strong entries.
I believe local contest participation will rebound if it becomes evident there will continue to be at least one week-long championship competition each year at an adequate site within reasonable travel distance. Serious modelers are less inclined to build large gas models, buy the latest engines, and spend time on hookups if their expected competition is only a handful of local entrants. A good week-long national event restores incentive.
If this philosophy rings true, it may explain why some past champions have skipped domestic competition in favor of more prestigious and less controversial FAI programs. Let us hope the new AMA/NFFS championship arrangement alleviates past problems. Time to bury the animosities of the eighties and move into the nineties with optimism.
Free Flight: Duration — Tips and Techniques
TE tip (stability under high power)
Modern Schnuerle-engine-powered Free Flight gas models can be extremely fast and leave little margin for error under power. Increasing engine power in an existing airframe can introduce strange behaviors.
Case example: a 600-sq.-in. model started with a K&B Greenhead .19 and later had a .40 cu. in. screamer installed. The design required structural and aerodynamic revisions to accept the larger engine.
Gilbert Morris offers a useful diagnosis and fix for models that race horizontally or begin an "outside loop" under power:
- Many troublesome stabs have the trailing edge chiseled away on top rather than continuing the upper-surface contour to the rear. At higher speeds the flow may attach to the beveled portion and produce unexpectedly more lift, causing the model to dive or behave erratically.
- Fix for a completed stab: add a balsa wedge on top to finish out the upper contour of the stab surface.
Coupled with wing-flex issues (see "FF Duration," April 1986), this may address many of the problems caused by upgrading engines without redesigning the airframe.
Rubber power — rear motor peg anchors
Following my last column on retaining rear motor peg anchors, Otto Curch sent a couple of proven methods:
- Balsa swell method: Cement soft balsa blocks on both inside sides of the fuselage opposite the motor peg holes. Apply moisture into the hole so the balsa swells, decreasing hole size and snugly retaining the motor peg. Reapply moisture if the peg becomes loose again. The balsa blocks also help retain the rubber motor peg anchors in the sides of the hole.
- Rubber-band notch method (used by Bud Romak): Saw notches on the outboard ends of aluminum-tube motor pegs and install the pegs. Hook a rubber band into the peg notch on one side, stretch it halfway around the fuselage, and hook it into the notch on the other peg. This provides a quick, visible retention method when you're rushing to launch.
Indoor flight: torque and rpm (brief overview)
Torque vs. time:
- Three important torque values exist for an indoor flight: launch torque, level-flight torque, and critical torque.
- Begin with launch torque; the model climbs until torque returns to level-flight torque. The torque of an unwinding motor then continues to drop, passing through critical torque — the minimum torque required to keep the prop actively pulling.
- When torque falls below critical, the prop must be pushed to keep RPM up and the model descends faster. With the proper rubber and prop match, touchdown should occur just as critical torque is reached.
RPM vs. time:
- A properly wound, no-touch indoor flight with optimal trim shows an RPM rise proportional to climb until level-flight torque is reached. From that point until touchdown, RPM is stable unless disturbed or critical torque is reached. Such a flight is technically perfect — though winners also depend on hall conditions.
Practical winding tip:
- Instead of underwinding, wind the motor nearly to maximum stress and then back the turns to your desired setting (e.g., to "C") using reliable winding techniques. The motor will then have D turns and more stabilized torque, yielding repeatable flights.
Alternative approach:
- Jim Richmond routinely flies this way. While he will ceiling-scrub when necessary, his mastery of trim, design, flight strategy, and hall meteorology usually wins without touching the top.
Microfilm time
- Best season to pour microfilm is winter. Pouring in midsummer risks sheet breaks due to solvents not fully evaporating.
- A remedy: use a small battery-powered fan to gently agitate the air over the poured sheet for two to three minutes. The agitation helps solvents evaporate and reduces sheet breaks. Less violent agitation (e.g., stirring with a spatula) also helps.
Corrections and the domino effect
Errors in publication can trigger chain reactions of confusion. I prefer to follow up with corrections promptly rather than point fingers.
First, I omitted the AMA Class C Gas results from the '89 USOC box scores published earlier. My apologies — here are the corrected results.
1989 NFFS/USOC Box Score — C Gas (Open)
- Russ Snyder, Universal City, TX — 1,758 seconds
- Ed Keck, Webster, NY — 1,650 seconds*
- Charles Caton, Montgomery, AL — 1,586 seconds
- Marvin Mace, Seguin, TX — 1,002 seconds
- Bill Dunlop, Greenville, PA — 750 seconds
*Note: Ed Keck posted 1,650 seconds for second place before official flying hours closed, then went on to add 726 more seconds to better the deadline and establish a new AMA Category III C Gas Open record (cumulative 2,376 seconds).
Yours truly regrets the omission and the resulting confusion.
Transcribed from original scans by AI. Minor OCR errors may remain.
