Can a glider with electric motor qualify as XC - RC Groups
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Nov 03, 2017, 01:12 AM
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Can a glider with electric motor qualify as XC


Simple question/ do the FAI rules allow to fly a F5J type plane where you launch using electric motor instead of a winch??
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Nov 03, 2017, 09:16 PM
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Quote:
Originally Posted by marios
Simple question/ do the FAI rules allow to fly a F5J type plane where you launch using electric motor instead of a winch??
Mario

I just read thru the FAI Sporting codes and the AMA Rules and Regulations for RC Soaring. I believe an electric motor would NOT be permissible for GLIDER records. Below is an excerpt from the FAI Sporting Code, Volume ABR, Section 4C, section 2.2.7:

2.2.7. Launching:
a) The model aircraft may be hand-launched or take off from the ground for record attempts in any
category except seaplanes, the launcher standing on the ground. Aerotow is not permitted.
Seaplanes must take off from a water surface. Model aerostats must take off from the ground.
b) For free flight a glider is launched by means of a cable of maximum 100 m in length. For radio
controlled flight a glider is launched by means of a cable of 300 m maximum length. Launching of a
glider may be carried out with the help of various devices such as winches, single or multiple pulley
trains, or by running etc.
To facilitate observation and timing the cable must be equipped with a
pennant having a minimum area of 2,5 dm2. All types of auxiliary stabilising devices are forbidden.
c) A parachute may be substituted for the pennant provided


Also, the AMA rules and regulations for Soaring appears to not allow electric self launching. The "National RC Sailplane Records" section of the AMA "Rules and Regulations" states the following:

The model may be hand-launched or launched by means of a line (hand tow, hi-start, or
winch) with a maximum launch length of 300 meters (984.25 feet). Hi-start
can be any combination of elastic and line, but stretched length for
launching cannot exceed 300 meters (984.25 feet). The towline must have
a pennant or parachute of suitable size and color to enable officials to
determine when towline release occurs. No other type or form of launch is
permitted. The launch equipment must be ground based.
Once released
from launch, no other propulsion of the model is permitted.


This is important because in order for the FAI to recognize a World Record it must first be certified as a National Record.


The FAI rules do allow for an electric motor in categories other than Glider. If the model has an electric motor I believe it would have to be classified as an aeroplane, not a glider. The category would be F5 open. Refer to the FAI Sporting Code, Volume ABR, Section 4C, Table 1. Gary Fogel recently set the Goal and return record for Electric Aeroplanes with what looked like a glider with an electric motor in the nose.

John
Nov 05, 2017, 10:38 AM
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I believe the League of Silent Flight also excludes motor gliders.
Nov 05, 2017, 06:11 PM
Sagitta Fanboy
Quote:
Originally Posted by jollyroger
I believe the League of Silent Flight also excludes motor gliders.
Electric motor-equipped sailplanes with ALES limiters are allowed for the eSAP, including the 3 XC tasks, but SAP tasks must be line-launch, hand-launch or slope.
Dec 13, 2017, 11:47 AM
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kuiperJ's Avatar
Questionable whether you would be awarded your 25, 50 or 100k pin but you still would get respect from the community (at least mine), let's say sub 1 minute of motor use or a ALES limiter to be fair.
Dec 13, 2017, 12:53 PM
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Quote:
Originally Posted by mawz
Electric motor-equipped sailplanes with ALES limiters are allowed for the eSAP, including the 3 XC tasks, but SAP tasks must be line-launch, hand-launch or slope.
Okay, Thanks.
Dec 13, 2017, 01:07 PM
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Remove Propeller. Install tow hook. Launch from tow line. Voila! Now its a glider.

JDK
Dec 14, 2017, 10:23 AM
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kuiperJ's Avatar
Quote:
Originally Posted by JerryK
Remove Propeller. Install tow hook. Launch from tow line. Voila! Now its a glider.

JDK
For pure competition just the drag of a folding propeller matters but for a slightly more casual XC flyer why make things unnecessarily inconvenient and overly complicated trying to tow line launch? Soaring underweight has a tendency of being more of an issue than flying a little overweight. By this logic you are going to have to pack something up there whether it be lead, ball-bearings, fishing sinkers, a stupid heavy battery. Might as well make it something useful like a motor.

The only real counterargument to my "useful weight" standpoint would be water ballast. You can dump water weight but you can't dump motor weight lol.
Dec 14, 2017, 12:32 PM
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Mr. Kuiper
Just how much X/C flying have you done? I've set WR's in both sailplane and Electric XC.

Remove the Prop and let a shaft stick out, Drag is minimal. Put in a Hook mount and tow hook and learn how to fly off a winch or cartow. It is not that hard.

JDK
Dec 14, 2017, 05:00 PM
Balsa breaks better
Thermaler's Avatar
Quote:
Originally Posted by kuiperJ
"useful weight" lol.
A larger battery is the only useful weight I know of. A motor that can only be used to get to launch height is just dead weight.

Joe
Dec 14, 2017, 05:50 PM
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kuiperJ's Avatar
Quote:
Originally Posted by JerryK
Mr. Kuiper
Just how much X/C flying have you done? I've set WR's in both sailplane and Electric XC.

Remove the Prop and let a shaft stick out, Drag is minimal. Put in a Hook mount and tow hook and learn how to fly off a winch or cartow. It is not that hard.

JDK
Sorry I'm new here; is this thread strictly for FAI sanctioned XC or is this a thread for XC glider enthusiasts? If it's FAI only then don't mind me, I have simply stumbled into the wrong place, if it's a thread for people who enjoy RC XC then motoring to altitude is hands down the better option. Better unless you care about the drag of the folding propeller, for some reason you think that lighter (flying minus the motor weight) is better, or you are not bothered by the inconvenience of hauling a bunch of tow-line stuff out to the field and setting it all up.
Dec 14, 2017, 07:27 PM
Registered User
Quote:
Originally Posted by kuiperJ
Sorry I'm new here; is this thread strictly for FAI sanctioned XC or is this a thread for XC glider enthusiasts? If it's FAI only then don't mind me, I have simply stumbled into the wrong place, if it's a thread for people who enjoy RC XC then motoring to altitude is hands down the better option. Better unless you care about the drag of the folding propeller, for some reason you think that lighter (flying minus the motor weight) is better, or you are not bothered by the inconvenience of hauling a bunch of tow-line stuff out to the field and setting it all up.
I believe this forum is open to anything having to do with XC soaring, including electric launched gliders. I know I enjoy reading about anything related to XC.

In the past we have had discussions on whether to allow electric launched gliders in contest. As CD for past Cal Valley XC events I have announced we would allow self-launched gliders, although none were actually entered. I believe for the Montague XC event Dean has even promoted a separate class for self-launchers. I think it is good to encourage anybody to try XC with whatever type of glider they have. Not everyone wants to compete, but still may enjoy flying XC.

John
Dec 15, 2017, 07:55 AM
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jtlsf5's Avatar
As Mr. Krainock suggests, just take the prop off, install a towhook and move on. Leave your batteries in place to maintain balance.

My solution is similar. I modified an SBXC for electric launch and retained the piece of the fuse I cut off to install the motor mount. Plane still has the towhook. To fly non-electric I simply remove the prop and tape the nose piece back in place. Balance changes very little, it stays aerodynamically clean, and by using a smaller battery in place of the 5A one (located over the CG) I use for the motorized version the plane is a bit lighter for strictly winch launch flying.

There is always a reasonable solution to any problem.

JT


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