Martin Harris - Moderator

It would certainly be sad if such attitudes and obvious misunderstanding of the NOTAM system jeopardises the hard work behind the privileges granted to the BMFA.

From the latest CAA CHIRP publication - an outlet for anonymous reports to help enhance safety - I’m very concerned if the report reflects the attitudes of the club concerned accurately: Initial Report I was planning a flight from [Airfield 1] to [Airfield 2]. As part of my planning I saw a NOTAM raised in the [Town] area, 4nm diameter, surface to 3200ft amsl, 24/7, for the flying of drones and model aircraft. It’s a very congested piece of airspace constrained laterally by [Airfield 3] MATZ and [Airfield 4] ATZ. Vertically it is adjacent to the London TMA. I always try and follow the GASCo advice of take 2 miles laterally and 200ft vertically, so I was pretty interested in what might be out there to bump into. As a courtesy, I elected to call the number given to see if they were operating. The person’s tone at the other end was demeaning, became insulting and finally threatening by demanding my details because they were going to immediately contact the CAA. As the conversation had become threatening, I advised I would not continue and terminated my call. I’m glad I was operating as a rear-seat pilot not as P1 because by this point I was thoroughly irritated and distracted. Their understanding of NOTAM use and the rights they give is different to mine. They considered that: the NOTAM had been raised by the CAA to protect my life (if in error I apologise but I thought NOTAMs were raised by the originator); I was not permitted to fly through that airspace; there is no requirement for the drone operator to maintain lookout; the drones are not required to be kept in line of sight; they had no concept that they were also responsible for separation and avoidance action; in no uncertain terms they advised that I should hold outside their airspace and climb above before proceeding; they could fly their large heavy drones 24/7 with no consideration of other airspace users; and they had no requirement to manoeuvre away should they sight an aircraft. I remain certain much of the above is not true. I believe the size and use of this NOTAM’ed airspace is inappropriate and have raised that direct with the CAA. CHIRP Comment This report highlights misunderstandings that might exist about NOTAMs versus restricted areas and TRAs. Although published by NATS on behalf of the CAA, NOTAMs are compiled by the requestor of the activity. In this particular case, the NOTAM was a navigation hazard warning with no requirement to avoid it although sensible to do so given the activity likely to be conducted within with small models/drones. For their part, those operating drones/UAS within such NOTAM’ed areas still have a duty to avoid collisions with other aircraft and so they must maintain visual contact with their drone/model at all times – all airspace users have a duty to avoid collisions and must give way to aircraft to the right of their own. Given the often small size of drones/models, there is extra importance in drone/UAS operators avoiding aircraft that they see given that their drone/model will likely be very difficult to detect by an aircraft pilot. In short, unless specific arrangements have been made to operate BVLOS[1] (which requires a TRA at present), a model/drone operator is required to maintain lookout (either themselves or by an observer if using FPV[2]) and must keep any model/drone within their line-of-sight. [1] BVLOS – Beyond Visual Line of Sight. [2] FPV – First-Person-View, i.e. using heads-down video or virtual reality goggles. The NOTAM itself was poorly drafted with a number of errors in heights. The upper limit was erroneously described as the surface altitude in one part and 2500ft agl in another (implying a top height of 3200ft amsl). The intended top-height was 1500ft agl (2200ft amsl) and this was corrected in a subsequent issue of the NOTAM. Whilst we’re all prone to mistakes and errors at times, it shows the importance of understanding the NOTAM compilation process and double-checking any entries to make sure they are correct. NATS have produced NOTAM Guidance Material (see also QR code), wherein Paras 3.2 and 3.3 (reproduced below) give an explanation of how to decode NOTAMs. Although many electronic navigation and planning aids do this automatically for users, those compiling NOTAMs need to understand the various entries and what they mean.

I’d love to see that video without the music. Some excellent flying!

Get well soon Matty and fingers crossed for a full recovery.

I thought it was just me. I’ve had numerous punctures over the years - everything from screws, nails, blackthorn, to the operating bar from a Yale lock! The first thing I did when buying a new car was to buy a spare wheel and jack to replace the stupid inflation kit - use of which means that most places won’t repair a puncture! One wouldn’t have been much use when I slashed a huge gash in a tyre on a stone while pulling into a Cornish passing place a year or so ago.

Only the receiver crystal is dual/single conversion and the correct type needs to be used for either a single or dual conversion receiver. Unless your receiver is marked as dual conversion it’s almost certainly single conversion - in the case of Futaba, SC normally used orange aerials and DC had white ones.

Best not to charge your diy conversion electric car in the hall then!

I assume you’re referring to 18650 size cells? Remember that the voltage quoted is a nominal figure and depending on the type of chemistry, will typically be around 4 - 4.2V (8 - 8.4V per 2S pack) fully charged. There are high voltage servos and many receivers are tolerant of such voltage but most servos are likely to have short lives run without a regulated supply.

Very sad. A well respected contributor.

I’ve bought a few odds and ends from Temu - all have arrived and were as described. With any of these Chinese sites e.g. AliExpress, they are only as good as their sellers so it pays to take care what you’re buying.

Thanks - my lash-up is fine for flying so I’ll keep hoping one falls into my possession as it looks like the DB one would need a lot of modification. I’m still keeping a couple of fingers crossed that my original might find its way home somehow before the model finally expires!

I thought it was odd that you were asking such a question! I’d assumed he’d be using a 4 cell holder but I suppose he might be using a 4.5V pack if they’re still available? Haven’t seen one in years…or a 90v battery either for that matter. I wonder if they’d even be allowed to sell them these days!

Dry cells are non rechargeable cells (e.g. torch batteries) nominally 1.5V They come from many sources - some better than others (weight is often a clue) and with different chemistries (e.g. zinc-carbon, zinc-chloride, alkaline) so perhaps may suffer from greater voltage drop under load.

Isn't this a simple throttle to elevator free mix on virtually any programmable transmitter? Experiment with percentage mixing until there's no (or the desired amount) of trim change and, if the transmitter has the capability, use output curves for fine trimming if required.

I'm unaware of any action but there was a server change earlier - perhaps something to do with that?

Millennium bug 24 years late?

Can’t say I’ve had many problems with the wire cable linkage Frank, and I feel it gives a measure of shock absorption.

An elevator-less landing isn’t impossible but is rather stressful…as I found out after flutter removed the clevis from the elevator servo of a model I was test flying for a clubmate. In fact, I did know of one full size glider pilot who managed to land from a rather traumatic winch launch without damage after failing to connect the elevator (pilot and design fault) using camber flaps to control pitch. As he was a serving cleric, there might have been an element of divine intervention!

This is my heavily modified (some accidentally and some deliberately) and much abused nose area with a ply subframe linked to the battery mounting plate, during repair - excuse the unfinished glass clothing! P.S. I don’t suppose anyone has a spare cockpit cover from a deceased model? Mine was lost in wooded countryside so I’ve had to make a DIY replacement.

How about drilling/reaming a hole in the correct place and pressing in a 1/4” bearing roller? Different lengths available… https://simplybearings.co.uk/shop/Loose-Balls-and-Rollers-Loose-Steel-Rollers/c23_5043/index.html?selection=Loose+Rollers

Almost certainly not. Any BVLOS flight would be subject to stringent regulation by the CAA and permission would be unlikely to be authorised to an individual hobbyist. Xeno - as this is primarily a UK based forum (although we welcome and enjoy contributions from members worldwide) where such operation is illegal, potentially unsafe and very much to be discouraged, there is unlikely to be much knowledge or experience of autonomous operation - hence some of the earlier confusions.

If your nose is structurally sound then you could simply re profile it with lightweight filler and cover it with light glass cloth. This area carries the nose leg if you have the retracts and can benefit from internal reinforcement if you’re making any more major repairs.

One factor that hasn’t been mentioned is that aerofoils work differently at different scales so simply scaling one may not give best efficiency. However, at our normal sizes and build accuracies, I’ve never felt that aerofoil choice (within reason) will make very much difference to performance unless it’s for a specialised competition model.

I’m thoroughly enjoying these postings, showing what can be achieved with some fairly basic equipment and ingenuity. Although I went to a grammar school, we had a wonderfully equipped metalwork shop with, along with the ubiquitous Boxford lathes, much larger Colchester and Cardiff ones, several vertical and horizontal mills, surface grinder, shaping machine, power hacksaw, forging, welding and casting equipment - all of which which we were encouraged to use by an enthusiastic and supportive teacher with industrial experience - both during lessons and for various projects after school hours. Although I didn’t go into mechanical engineering, this grounding gave great basic skills to build on in later life in activities such as aeromodelling and vehicle restoration and gave the impetus to acquiring some basic machine tools of my own which have been, and continue to be, so useful in a myriad of activities. Yes, we were exposed to dangerous equipment and the odd splash of blood may have dripped onto the floor, but safety was not only taught but enforced with vigilance, free from the shadow of formal risk assessments, method statements and potential litigation hanging over the school staff. We, in turn, learnt to take responsibility for our actions - something I fear is not always the case with modern generations. Hope to see this engine running before very long!

Correct - and it was flagged to the site owner early this morning.