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President: Dave Ward Esq
Vice Presidents:. CJ Norman, Terry Kitson
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Tony Major: Chairman |
Fred Clarke: Secretary |
Dave Hodges: Treasurer |
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Ian Kenyon |
Geoff Ward: Safety Officer |
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Keith England: P.R.O. |
Alan Dobson: Social & Membership Secretary |
It is with great sadness that I have to notify you all of the death of our President Dave Ward at the young age of 61. Dave passed away after an illness that he had battled against for over 15 years.
Dave was always a staunch supporter of the club and until fairly recently an active builder and flier. You never heard him complain about his health, he used to shrug it off in a casual way saying it was “just one of those things” or words to that effect.
Over the years he always volunteered for any job to be done whether at the field, or for the annual public shows we used to hold, the last of which was at Brooklands in 2002.
In particular he worked hard making props for the "Air Raid" section and was very innovative at making buildings, hangers, tanks, ships, planes, vehicles, etc to be set on fire and blown up on show day to everyone's delight.
We have all lost a good friend and our sincere sympathy goes out to his widow Caroline, his sons Geoff and Paul, and all the Ward family.
Dave's funeral will take place on Friday 27th July at 1:15pm at Randalls Park Cemetery. No flowers please, but should you wish to give something in commemoration of Dave's life. Geoff would be pleased to accept any donation made payable to the “Aneurysm Research Group”.
Geoff is also taking part in a sponsored 40 mile cycle ride on 2nd September from London to Windsor. All monies raised will go towards research into this little known disease. Any members wishing to sponsor Geoff for this very good cause should contact him on 020 8397 2257.
Flying Fields - we are now back at Merstham thanks to the efforts of Gus and a handful of members who turned up on 7th July and who were almost stung and bitten to death by the nettles and insects. We hope to return to Downside on 22nd September and have our fly-in and BBQ (that was postponed from 1st July due to dreadful weather) on 30th September.
Club Room - the cost per evening at Nescot is going up to £40 in September which works out at about £4 per member based on average attendance. This is excessive and unreasonable and I feel we should look for a hall where we could fly indoor models in the winter months. It could be a community hall, a Church hall, or a large room over a pub. The hall at Bookham that we used cost £16 and one could make tea but it is only available on Monday's and is a bit small for indoor models. So keep your eyes and ears open to help us find something suitable. If we did find somewhere and those members who fly electric in the summer could use the field and we could meet in the local pub afterwards for a noggin and a natter.
Finally some good news - The committee are pleased to announce that on 30th June 2007, Chris Norman agreed to be a Vice President of the club. Thank you Chris.
Tony
16/09-Sun Club outing to Croydon MFC show at The Hop Farm, Kent.
22/09- Sat Return to Downside Flying Field (Postponed - see members news )
30/09–Sun Fly-in & BBQ at Downside. (Cancelled - see members news )
14/11-Wed AGM.
01/12-Sat Christmas Dinner.
After the serious incident last summer, where an idiot who had been shooting in the next field drove across the active runway, we intend blocking the runway approach. If you arrive after 1pm (or the barrier is up) you will need to either drive down the farm track or park at the entrance end of the field under the large Oak tree. Even if the barrier is not up, check carefully whether anyone is flying; if so, stop well short of the approach and sound your horn. Drive onto the runway only once you are waved on (or use the track).
A significant number of members have small electric helicopters now and at least 4 have larger machines. However a number of members have complained about helicopters being flown at the same time as 'planes and the committee realised the same issue goes for gas turbines. It had been decided that when either jets or helicopters are present a couple of 15 minute slots should be allowed for them. We will see how this goes and discuss further at the AGM.
The death of the Sandown Symposium, overdue in many people's minds, has left a void in the calendar that just cried out to be filled. Enter the Thames Valley Model Show, Saturday 19th May at Blackbush Airport.
1/2 sized Pitts is actually hovering
in this shot
(shows the wind strength!)
One of my friends flies from Blackbush; we were both puzzled where a model show could be held there without being a danger to the full size aviation? The answer was simple: the airport owner is, apparently, a member of the local model club so he shut the airport for the day. Aircraft had until 10a.m. to depart and were allowed back after the show finished.
One of the biggest criticisms of electric flight is "they don't sound right". A large scale electric Lancaster and Hornet, answered that with on board sound systems linked to their throttles. Not only did they sound as real as they looked with the engines throttling up and down correctly but even made the right starter sounds as they 'fired up'!
Beautiful Electric Lancaster Comes Into Land - Shame I can’t reproduce the sound of its 4 Merlins idling!
The show was excellent; flying was on the main runway, jets, lots of very big stuff and with parking and stands on the Blackbush market site so loads of parking and good toilets.
There were not as many traders as I'd hoped and another puzzle was the large and excellent display presence from Al's Hobbies but no trade stand. Turned out their lorry broke down on the way to the show.
Some of the models really needed the full size runway - Zlin put on an impressive display!
"There I was upside down with nothing on the clock" - The jets now have smoke systems as well
While on the subject of electric flight a few words about LiPo's (Lithium Polymer batteries).
LiPo's and brushless motors have, between them, revolutionised electric flight to the point that they more than match glow engines in all but price – and that is reducing constantly! However, there has been a fair few scares about them being prone to bursting into flames which may put people off.
In fact, if you look at the incidents closely there is only one common element – carelessness!
Simple rule of thumb is that LiPo's contain almost as much energy as petrol and should be treated with the same respect.
By the way the ballooning is oxygen being vented so, if they do catch fire they are very difficult to put out and the fire itself creates oxygen!
However, LiPo's are an excellent power source no less safe than that gallon of 5% fuel you don't even think twice about. Don't be put off by the problems you have heard about, just treat them with care and consideration.
None of the following is absolutely necessary, but to get the very best life out of your LiPo's aim not to discharge more than 80% of capacity and try to never discharge more than 90%. Charge at a lower current when not in a hurry, say 1/2 C i.e. 1 Amp for a 2000mAh battery, use 1C (2amps in this example) only when you need them charged quickly.
When a LiPo is brand new it is important to charge and discharge it gently a few times and this is a good way to aim for that no more than 80% target. Fly a quite short but typical flight and note how long it is with a timer. Charge the battery with a decent charger which will tell you how many mAH it is putting back.
Say you are using a 2000mAh battery and a 3 minute flight consumed 400mAH
80% of 2000mAh is 1600mAh – so this is the max you want to aim to charge back into a pack.
If a plane consumes 400mAh in 3 minutes then it will consume 1600mAh in 12
minutes (1600/400) x 3 minutes.
Try to keep your flights to 12 minutes max and you know you have at least 1½
minutes in reserve if you need it and still stay below 90% use.
To check this, and still protect your new battery, don't jump straight to 12 mins. Aim, say, for a couple of 8 minute flights and check that the charge fed back into the battery (around 1070mAH in this example) is still around the correct figure or adjust your expected flight time accordingly.
You’ve almost had to have been on the moon not to have noticed the arrival of these new beasties, but you may just have decided it is technological gobbledegook and ignored it!
So let’s say it right up front: these are, more or less, the holy grail of model radio control: the almost idiot proof, interference free radio - and at a very reasonable price - around £240 for a fully programmable 7 channel, 20 model memory Spektrum DX7 set with 4, good spec, digital servos. A separate charger is needed (£10).
I’ll discuss this in more detail below, however there really is only one serious danger in using these radios so let’s get that out of the way first:
This danger is not the newcomer but the rest of us who are likely to eventually have both 35MHz and 2.4GHz radio. It is going to become oh so easy to forget to raise your aerial and, later, just as easy to switch on a 35MHz transmitter without checking the frequency is clear. So, if you do get a 2.4GHz set, you WILL put a black pennant on it and You WILL record it in the field book and you WILL put a peg on the top of the board. These activities seem pointless for 2.4GHZ until you realise it may prevent you having, or causing, an accident when you next use 35MHz.
So what is all the fuss about?2.4GHz is the frequency used for wireless computing-usually with just 10mW output and a range of 100 yards or so. No use for aircraft until a law change last year allowed 100mW output with a range, now, of several miles. However model cars have been able to use the 10mW version for some years and even with the weak signal have seen impressive performance - not only that, but they’ve ironed out all the bugs for us as well! 2.4GHz is spread spectrum so, like a military radio (or more importantly your mobile phone) it chucks signal out over a broad band of frequencies and encodes it, using a serial number built into the transmitter in such a way that it appears to be noise to every receiver other than the one which knows that serial number. As receivers reject noise, even two transmitters on the same frequency are unlikely to interfere with each other. Jamming, deliberate or otherwise, is darn difficult! What this means is that you just switch on and go (number of aircraft already flying allowing!) The radio will sort out a clear frequency and transmit on that. Around 40 radios can be on at the same time and, if there isn’t a clear channel it won’t transmit. Better still, electrical noise in our aircraft such as metal to metal or electric motor noise has much of its energy around 35MHz: it has virtually NO energy at 2.4GHz so glitching really should be a thing of the past. I, personally, won’t consider using 35MHz in electric planes of any size from now on. |
Tiny 6 channel 'Park Fly' receiver weighs 7 grams - has a very good range for a park fly! |
No worry about interference or being shot down or glitching from noise even though the aerials are just 3cm (1.2") long - so no long trailing aerial either.
To add to the above, Spektrum the American manufacturer, code the model number as well as the transmitter serial number into their receivers so, if you select the wrong model number (the DX7 has 20), the receiver just sits there in fail safe. Futaba don’t offer this facility in their current 2.4GHz sets. Can a radio get any more idiot proof than that?
So what happens if you buy another receiver or want to use one on a different model number? The transmitter has to be "bonded" to the receiver. This is the process whereby the receiver 'learns' the transmitter (and model number) to work with. On the Spektrum this is done by plugging a small servo type plug into the charging socket of the switch harness and going through a simple set up procedure. This also sets the servo failsafe positions. This only needs to be done once in a model unless resetting the failsafe positions. Futaba do the same thing with a button on the receiver, arguing that there is no plug to lose. However, you can always get to the charging socket; a receiver may be buried in the model.
The comparison between Futaba & Spektrum is interesting, Futaba advertise 15 years experience in 2.4GHz technology, yet were beaten to market by Spektrum and you get a real feeling of them trying to find ways around Spektrum’s patents. JR currently looks as if they will simply adopt Spektrum’s technology. Both companies say that response is much faster than PCM although you might have to be Luke Shaw to notice!
So what are the downsides?
Bottom line, 35MHz is going to around for a long time and will get better as less people use it. If you are on a tight budget there are going to be some real 35MHz bargains soon! If you are not on a tight budget is it worth buying any more 35MHz equipment? Time will tell.
