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Category: Archive 2013

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1. On F1Q rule making
2. Its more than Q
3. Lost in the Hills
4. Budapest Cup?

On F1Q rule making

The April CIAM meeting in introduced minor changes into the way the energy of Q models without energy limiters (on-EL Q) models is estimated, using the mid motor estimate rounded down to a full second. Another change was to measure the energy of Q models with energy limiters (EL-Q) statically. (I call these devices SET - Static Energy Testers.) This is a reason able approach because it measures the model’s overall consumption of energy, which is identical to consumption in flight and it does not depend on a freshly charged battery. In fact, the first SET is currently being readied for market. Both proposals were featured in FFn’s February issue.

The same FFn had another (shadowy) proposal:  … “Another German proposal on part (a) [EL-Q models] goes into greater detail on system organization and emphasizing that the timer must be independent of the energy limiter.  It refers to the techniques used in FAI F5 electric models”.

I was able to obtain a boot legged copy of the CIAM agenda. This German proposal was stuffed into an appendix which I did not have.  The meeting was reported in FFn’s May issue. The free flight technical committee meeting was attended by 14, three from the UK, two from Germany and non from the US. “… Most the proposals were from Germany and concerned specifying the architecture of the system and also the means to monitor and confirm the energy used. F1Q flier Andreas Lindnerwas present to support their proposals and demonstrate the equipment. Their proposal was accepted by the meeting with a close FFTM voting of 3 in favor, 2 against and 4 abstentions.  A practical concern was that their insistence on the EL being separate from the timer rules against the alternative integrated system developed by Italy.”  … “All these changes were accepted by the Plenary meeting …”. 

The published Q rules for 2014 mandate that the EL be separate (physically) and be responsible for shutting down the motor.  Almost all Q fliers are dead against any rules defining Q’s internal electronic architecture, as evident on the NFFS site (www.freeflight.org).

There are two underlying issues. First, the requirement that the EL shut down the motor presumes that the programmed energy is identical to the used energy. But we know that motors don’t shut down instantly, so this amount of energy is just ignored. Another problem is that straight climbing Q models require an early function (functions that kick in just before the motor is cutoff) such as bunt or rudder. It turns out that these models have difficulty bunting due to their deceleration towards the end of the climb as their battery’s voltage is falling. Some fliers have increased the downward motion of the stab to pitch the model over. Others, like me, also use early bunt and rudder. I program my EL to 95% of the allotted energy; it then signal the e-timer which immediately kicks in the bunt and rudder and cuts the motor after a small delay. It’s currently legal because a statical energy test proves that the overall energy consumption including the bunt and stopping the motor is under the model’s energy ceiling.

The second issue is why a ‘game changer’ was allowed to slip through a back door. The cutoff time for rule proposals is November 15^th. The German EL architecture proposal was described in the FFn February issue in the most general terms.  It is also evident from the FFn May issue that participants viewed it as a product change, one that would obsolete the Italian Sidus EL, not as something that would radically change the internal electronic architecture of Q, solving an non-existing problem!  A SET (Static energy test) is sufficient to assure that a model is energy compliant, irrespective of the internal electronic architecture. In the example above, an EL could signal 50% of the energy to the e-timer, the e-timer in turn could delay shutting the motor for 3.75 seconds and the model would still satisfy its energy budget. (Imagine that we could train lizards to shut down the motor. Who cares how many lizards are performing this, if at all.)

I’m not against people proposing game changes; that’s their prerogative. (For example, in U-control, someone could propose using three lines.) But game changing proposals should ideally be quarantined: included as provisional non-binding status for at least a year, giving fliers the time to digest and understand their implications. A razor thin majority with so many fence sitters on a highly technical issue should have raised a red flag.

Maybe F5 models need separate ELs, but how is this related to Q?

Aram

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