FXRES start height for electric F5L models.

[Lawrence D]

There has been a suggestion to align the FXRES start height for electric gliders with the FAI F5l rules- i.e. change from 100 metres to 90 metres.

Aspects which support the proposal include:

• Alignment with F5L rules would save resetting altitude device when flying in either class.
• People can operate at a set altitude for all competition flights

Aspects which support leaving 100m rule as is:

• Operation of FXRES and F3L/F5L competitions is so different anyway
• If its not broke don't change it
• Its not a big deal to change setting of altitude device
• 90 metres could make achieving max impossible in some typical UK brutal windy conditions
• More challenging for new soaring pilots to connect to lift and gain experience

The BARCS committee have discussed and would like to throw the question out for feedback from FXRES enthusiasts. Comments below please by 14th September

[Richard Newsham]

For me I would say keep it as it is at 100m.  I need to alter my Altis nano for 4 different reasons anyway. Monthly duration challenge, 90m FAI rules, 100m FxRES and F5J comps.

To give new starters every chance available, don’t take an extra 10m off them.  At a sink rate of 0.5m/s that’s potentially, in winds less that 5 mph, an extra 20 seconds flying to find a thermal.  6 minute maximums are great to achieve and give a great sense of achievement.  They have to be worked for as it is.

regards, Richard

[cirrusRC]

If we have any desire to move towards an fai style league then I say the more aligned to the rules now, the better. 

Personally for beginners, I think launching lower is more beneficial.  It's easier to see what the model is doing and how it responds to the lift.

Whilst you may find larger and stronger lift higher up, it's harder to establish what the model is actually doing and how it responds to your inputs.

[andyharrold]

Personally, having listened to both sides of the argument, I am with Richard and Alex Maxfield on this. Remain at 100m, build some confidence. 

Flying the monthly duration at 60m can be quite disheartening so the 100m is a pleasant change.

 

[Martin O]

I vote for alignment with f5l rules and set height limits to 90m. To me it makes sense. I think new competitors will then be be better prepared for a switch to the full rules.

Yes it will probably reduce the number of max flights flown but to put it in to perspective a 10% reduction in time is 36 seconds.

EDIT: In light of the discussion around CAM AMRT's (see the later posts), I now have no fixed opinion on 90m or 100m. I see pros and cons both ways.

[John Minchell]

I am strangely without any strong opinion on this.  Personally it doesn't matter to me which is adopted, 90m or continued with 100m.  I can see the arguments for both and they are equally valid.

I suspect the elephant in the room which needs much more immediate attention, rather than altering F5 launch heights is, does the class have a future?  Because looking at recent numbers competing (excepting the Nats) numbers are dismal compared with 4 years ago.  What needs immediately fixing is how to ensure there are at lease 12,15 or 20 competitors for every event. Otherwise clubs like Aylesbury will not offer their fields and disadvantage their club members for the day and there will not be any competitions.  I can see Manny doing the same with Buckminster too.  Where you may only be offered weekday events not weekends eliminating all the people still working.

So over to you.

John M

[MikevE]

I've flown only a very little F5L/FxRES, so my opinion isn't worth much, but KISS (known as keep it simple, stupid) is a principle I rather like. I'd go with the FAI rules to do this. 90m is still a massive launch by comparison with DLG flying, at least my own weak low launches, and it's still quite a lot more than the UK's best F3K launchers. I enjoy thermal flying when it's harder, not when it's easy. A slightly lower launch height makes things a little more testing. It forces us to be more observant of thermal tells before launch, which is one of the key skills in most thermal flying comps. 

[RSH]

I believe the current rules state that the model must contain a height limiter that cuts the power to the motor at either a height of 100 metres or after a 30 second motor run.  The CAM height limiters, which are simple to program to 100m,150m or 200m, would therefore comply with the current rules.  Moving to 90m would therefore mean that this type of 'preset height' limiter would be useless.   

In Kent, we are trying to get 2mRES off the ground.  In support of this, I have rounded up 6 of these preset HLs to ease both the cost burden and to overcome the recent  issue of buying new limiters.

In conclusion, please be mindful of the effect of any rule changes on equipment and costs.

Richard H

[cirrusRC]

Agree with John. The class has bigger fish to fry than worrying about launch height. 

I'd have no issues with people launching an extra 10 meters if their limiter didn't support 90 meters.   On the bungee side the launch variance is far higher than 10 meters and no one is worried about that.

[Pete in Northiam]

I don't (yet) fly F5 but at the Kent Interclub 2m "free for all" a few weeks ago, it was even more simple than FxRES: standard 15+100m F3L bungee or 100m/30s electric launch, time all from leaving the hand and combined classes for results. Worked very well with a mix of F3 and F5 flyers through the results table.  Incidentally my times from release to off bungee were 18 to 22s. 

[Martin O]

22 hours ago, RSH said:

I believe the current rules state that the model must contain a height limiter that cuts the power to the motor at either a height of 100 metres or after a 30 second motor run.  The CAM height limiters, which are simple to program to 100m,150m or 200m, would therefore comply with the current rules.  Moving to 90m would therefore mean that this type of 'preset height' limiter would be useless.   

In Kent, we are trying to get 2mRES off the ground.  In support of this, I have rounded up 6 of these preset HLs to ease both the cost burden and to overcome the recent  issue of buying new limiters.

In conclusion, please be mindful of the effect of any rule changes on equipment and costs.

Richard H

It's a valid point but I think you will find that CAM devices are not on the list of SF rules approved height limiters, so are already outside the current BMFA FXRES rules. Someone please correct me if I'm wrong.

Of course as a club you can fly whatever rules you want and maybe the SFTC could consider an amendment to include CAM devices as approved, specifically for FXRES rules. That is assuming the vote is for the 100m launch height to remain.

[mikef]

I'm out at the moment but I'll post my conclusions of an examination of the 'approved AMRT', problem this evening.   As I remember it, devices on the FAI list are included in the BMFA list automatically.  More later.

[cirrusRC]

From fai side all I could find was here

https://www.fai.org/page/ciam-edic

Which doesn't cover our class.

[RSH]

Hi all,

After some grubbing around, I managed to find the rules which, as stated, exclude CAM HLs.  Not sure why these are not allowed though.

See page 43

https://britishmfa.sharepoint.com/sites/public/Rule Books/Forms/AllItems.aspx?id=%2Fsites%2Fpublic%2FRule Books%2FRule Books%2F2024 SILENT FLIGHT RULES V2.pdf&parent=%2Fsites%2Fpublic%2FRule Books%2FRule Books&p=true&ga=1

[mikef]

Edited to take account of the non-display CAM AMRTs.

RSH,  have a look at the top of page 43 - that includes the EDIC WG list where you will find the CAM F5J device with display - so that version is 'legal' - the non-display ones are not.  You can't change the firmware on the CAM F5J so it can only be used in F5J.

There are effectively no F5L or F5K AMRTs at all officially approved.

I have attached the current FAI CIAM EDIC WG approved F5J AMRT list.  EDIC WG = Electronic Devices in Competition Working Group.

On their EDIC WG page, linked above by cirrusRC, F5L is not covered.  F5K has a heading but no list of approved devices.  Only F5J has a list of devices and these are specifically cleared using their individual F5J firmware.

(There is no height limit in F5J and no limit is allowed to be set.  The climb height is defined as the highest point reached between launch and 10 seconds after motor cut.  Your climb height is deducted from your flight score at the rate of 0.5 seconds per meter up to 200m and 3 seconds per meter above that.)

Since accurate timing and height measurement are required in F5J, I see no reason why the approved devices shouldn't suffice for the F5K and F5L classes which use height and time limits, if their non-F5J software is approved.

If I set my RC Electronics Multi 3 to a height/time firmware for eSoaring and F5L, it then reports FAI height as for F5J - a good zoom or launch into lift and this will exceed the height limit set.

I wrote to the BARCS Comittee on 27/6/24 putting the full details of this matter forward and suggesting that CIAM should be approached with the information - see AMRTs.pdf attached.

EDIC F5J Approvals.pdf AMRTs.pdf

Edited September 12 by mikef
CAM F5J display version specified.

[cirrusRC]

Begs the question why fai chose 90 meters in the first place for f5L.   Surely they'll either have to change it, or remove cam devices from f5L.

I don't know anything about cam limiters but sounds pretty clunky you can only choose from preset heights.  

[mikef]

I don't think they've really thought it through for F5L - that's why I'm asking, through the BMFA SFTC, for the subject to be reviewed.  The existing list is F5J specific - no height limit allowed.

[cirrusRC]

The other thing.  F5j only support cam with integral screen (so you can read launch height).

The cams sold by hyperflight have no screen and state 

"Note this device is not legal for UK eSoaring competitions run to BMFA rules as it does not include a logging facility."

[mikef]

Didn't know there was more than one CAM device - thanks.

[Martin O]

I think the idea of CAM devices Is that you buy a specific type to suit the rules that you intend to fly. I guess it's for those that understandably want a cheapish plug and play solution without the need to plug in to laptop or whatever to charge the settings.

Unfortunately that limits the flexibility to switch between different competition types and in the case of f5l there is no type that offers a 90m cut off. Hence my suggestion that should the SFTC vote to retain 100m cut off in the FxRES Challenge rules, then they could perhaps consider CAM devices to be legal specifically for that category.

But they would of course still fall outside the FAI f5l rules.

The types can be found here

http://www.soaringcircuits.com/