National Free Flight Society

SEN 2295

  1. John O’Donnell Memorial page
  2. Rumors
  3. Babenko F1C Proposal

John O’Donnell Memorial page

John’s Son has started a page:- http://www.jod.org.uk

Rumors
The reason why we printed Mike the Dino’s  GPS piece under the title rumor because it ia a comment by Mike about an as yet un-released product.

The link to the Sidus/Aeris web site is http://www.ffelectronics.com/ . No mention as yet a new GPS product

While other people have a FF GPS units under development at the moment you can get one as part of a Favionics Timer or as the Optimal Tracking stand alone unit mentioned a couple of SEN issues back

The questions ….

GPS ?  

From: Chuck Powell

Hi Roger
I have not heard about the gps mentioned on sen ? Can you tell me anything about it ? Weight ? Etc cell phone usable ?
Thanks
Chuck Powell
Benton Kansas

GPS – 2?

From: hobbyclub

Any website or link for Massimo GPS..?
Alberto

Babenko F1C Proposal
A number of F1C flyers and SEN received a F1C suggestion/proposal from Artem Babenko.  It is SEN’s understanding that this proposal is not currently before the CIAM but something that could be in the future and Artem is looking for support of other F1C flyers.

Class F1C. Maximum duration of motor run in 21st century.
Nowadays without exaggerations F1C model aircraft should be considered as a work-of-art among highly technological objects. With ultimate aerodynamic parameters and advanced design of high-power piston engines F1C models are built from composite materials and could utilize variable wing and airfoil geometry, geared engines and flight control mechanisation based on electronic timers and servos.

Evolution and dynamic development of technical characteristics of F1C models were accompanied with new technical restrictions throughout the years. Since the beginning of F1C class in early fifties one of the most important regulated characteristic is Maximum duration of motor run which was reduced from 30 sec to 5 sec in 1998. Starting from 2016 this characteristic has been farther truncated to 4 sec.

Due to obvious reasons the precision of 4sec motor run timing should be very high in order to accommodate contemporary rules. Possible systematic errors should be eliminated or minimized.

However over the years the methodological approach for timing the motor run for F1C models has not been changed. In practice the old-fashion “acoustical” method of timing is used which requires from competitors an additional reduction of motor run by 0.4-0.6sec for compensating sound travel from about 150m altitude.

With simple calculations everyone can verify that for 4sec motor run only this systematic error takes in average 12% of total motor run. It sounds as an unacceptable value.

A lot of improvements and developments in terms of timekeeping were successfully implemented for FAI control line models such as F2A and F2C but nothing in F1C where timekeeping is a crucial part of a competition process as well.

Nevertheless a simple solution to this problem could be suggested for the models equipped with electronic timers.

An electronic timer by itself is a precision device with time resolution at least 1/100 sec and an extremely high level of repeatability. Contemporary electronic timers have standalone pieces of equipment (programming modules) where all parameters could be visually checked and verified. Based on these facts the following procedure could be proposed for F1C models with electronic timers:

1. During Model Processing Procedure will be an option for F1C models with electronic timers to have a record of “timer settings” and “actual motor run”. Each motor will be run in front of two timekeepers and correspondent records for each model will be made.

2. During competition rounds timekeepers will have a right to verify timer settings before an official flight. Knowing the fact of sound delay, from the ground measurements two timekeepers should only verify that their readings are within 4.6 sec in order to comply with the rules.

Note that such amended option to the rules allows using full potential of F1C models within same regulations, mitigating errors during timekeeping and will not discriminate the rights of modellers with mechanical timers.