Peter Jenkins

Well BEB, guess what? That darned cylinder head to exhaust header came loose again! Luckily, it did not cause a dead stick and so I only noticed the looseness when I came to choke the engine again for the next flight. So, a well rehearsed pit stop later (nut done up to a tightness I can only describe as "as tight as I could possibly do it without causing any damage to the engine bearers and their attachments"! The silencer to header pipe joint, that is with the new type Saito silencer, is fine! I'll see how many flights I can make before the wretched thing works loose again! PJ @import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

I would definitely not use any fuel containing castor oil in a 4 stroke because castor can bung up the delicate valve gear in a 4 stroke. I only use synthetic oil fuels in both my 4 and 2 stroke engines. @import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

One other thing with a 4 stroke, avoid using fuel with castor oil. That clogs up the more intricate mechanisms found in a 4 stroke versus a 2 stroke. Most OS and Saito 4 strokes need 18% oil in the mixture. I run all my 4 strokes (and 2 strokes) on 100% synthetic oil fuel and, indeed, none other than Brian Winch recommends the use of 100% synthetic oil. Some heli applications need more oil - 20-23% being figures I've seen quoted.   The valve clearance is another interesting issue. Saito provide a gauge but this is so thick that you are better off using car feeler gauges (that dates me!). My Saito 180 has a recommended gap of 2-3 thou whereas the Saito "feeler gauge" is almost 3 times thicker. Remember that the engine crankcase is usually allow whereas the pushrods are steel so the gap will tend to get bigger as the engine warms up. @import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

I tested a delta wing (a flat plate aerofoil) in a smoke tunnel many years ago. I found that you could get the AOA up to 80 deg and provided that there was no yaw, the two vortices that sit just aft of the Leading Edge were quite happy. Even a few degrees of yaw would see the vortex on the less swept wing "burst" and therefore "stall" that wing.   The pronounced LE vortex appears to be what generates the delta's remarkable lift at high AOA . Of course, a propellor will alter the local airflow significantly although a pusher prop may not do so to anything like the same extent as a tractor prop.   So, deltas do not stall in the same way as a conventional wing and, provided they have enough power, could achieve very high AOAs. In reality, the drag will limit the extent to which you can achieve sustained high AOAs. On some of the latest fighters, they can pull very high AOAs for a short period so that they can point at a target and engage but only for a short period as full engine power is rapidly negated by the huge drag associated with this manoeuvre.   I think that weight is much less of an issue than the high drag that is associated with high AOIA flight. In fact, for all practical purposes, the limiting factor on AOA for delta wing aircraft is the amount of thrust they have. @import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

I came across some interesting facts in my last job about the FD2. Two aircraft were ordered and after the world speed record both went to RAE Bedford. There, one aircraft was used to calibrate the model in the supersonic tunnel and much of that work ended up being used in the EuroFighter development. The other FD2 had the ogival wing, developed by RAE Farnborough for Concorde, fitted to back up the aerodynamicists theories. So, the FD2 played a role far beyond breaking the 1,000 mph barrier and its legacy lives on in the EF Typhoon but sadly no longer Concorde!@import url(/CuteEditor_Files/public_forums.css);@import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

If you look carefully, the airfield seems to be surrounded by a valley so he was probably higher above the ground under him than it looks. It's still a great bit of exhibition flying but where did he practice it? Oh, yes, he's one of those old bold pilots I guess!@import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

Tim,   I had the self same experience with an AR 500 in my trainer that I was using to give a friend a taste of flying RC. I lost the link when I was around 800-900 yds away and luckily the aircraft was high enough to allow the system to re-cycle (or what ever it was doing) and regained control. I therefore brought it in closer and then lost control with the aircraft slowly rolling over and heading earthwards. Nothing I did had any effect and the aircraft crashed some 300 yds away. Having recovered all the bits, I reconnected everything and all the gear worked! I thought that the single Rx AR 500 might have been a bad idea and decided that I wouldn't fly my other AR 500 which is in my Bucker Jungmann.   However, two days later, I lost my Wind S 110 when it suddenly pitched nose down and headed earthwards with no sign of control being returned to me. This one had an AR 6200 Rx in it. I should mention that I was using a JR DSX9 Tx on both occasions. I should also say that I have never had a moments loss of link ever in the 2 years that I have been using the JR Tx with Spectrum Rxs.   I sent the Rxs back to Spectrum and received a note saying that both had no fault but that Horizon would replace both for my peace of mind. I sent the Tx back to MacGregor and they could find nothing wrong with the Tx but replaced the RF section as a precaution and for my peace of mind.   I am about to write back to both to say that my "peace of mind" has been shattered in the light of these two incidents and I would like a definitive statement from both that using a JR DSX9 Tx (which after all uses the Spectrum DSM 2 system) is fully compatible with Spectrum DSM2 Rxs. If that is the case, why was the radio link lost - what failure mode would result in this behaviour.   You have now suffered the same fate as me. We really must get to the bottom of this, although in your case you also have the DSM2/DSMX issue to resolve.   Be interested to hear your thoughts after you have had a think about what happened and, perhaps, linked up the system and checked its operation.   Peter Jenkins @import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

Well, due to a family illness, I didn't get to fly at the Nats but did fly the day before and managed a further 3 flights with the Saito and exhaust staying firmly attached. So, methinks that Mr Saito has come up with a design of a silencer that stays put without any need to resort to epoxy, plumbers tape etc. The same cannot be said for the exhaust pipe to cylinder head join where I used 5 min epoxy and which appears to be holding ..... at the moment.@import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

Having done an analysis of what I have spent so far and what I intend to spend to the end of the year, I was somewhat taken aback! While there were some exceptional costs, the majority of the spend was made up of purchases in the £30-£70 mark. It is all too easy to think of these as being "relatively minor" but they rapidly mount up and have significantly outstripped the "big ticket" items in the spend.   A very sobering experience and one that threw into focus the cost of 2 crashes caused by radio malfunction (2.4 GHz not 35 Mhz). @import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

I thought that mobile phones were either in the 900 MHz or 1.8 GHz bands. I was not aware of the 2.1 GHz band being used by mobile phones. Does anyone know for sure what are the bands used by mobile phones?@import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

Well, removing the standard Saito silencer, which proved very difficult, was a great mistake! The Weston Saito 180 can just would not stay connected despite using 5 min epoxy. So, I returned to the Saito 180 standard silencer. Despite using 5 min epoxy, and tightening up after the ground run, the silencer still worked loose and led to a succession of dead sticks.   Then decided to run the Saito without exhaust pressure and the first flight showed that it needed to be richer for vertical climbs. Second flight with the engine set richer resulted in the silencer unwinding itself completely. Since none of us noticed a sudden increase in noise I can only surmise that it fell off during the low throttle recovery phase!   Saito had sent me a Saito 150 new silencer (same as for 180) and I had noticed that this was of a different design, material and finish to the original one. Basically a cylinder with a boss at each end for input and exhaust and not with the intake set at an angle as the original. I thought this might be the result of difficulties in retaining the original exhaust so decided to fit and fly! As this new silencer does not have flats on its mounting boss, I could only grip it by hand and tighten up the lock nut. I had cleaned the thread and the face of the nut that would abut the silencer. I did not use any epoxy or plumbers tape - just au natural.   The ground run showed that the silencer had not loosened so I flew it twice and flew two aerobatic schedules. Result was that the silencer was still firmly attached! Well, I rather suspect that Saito has done us a favour by redesigning this silencer to make it stay on without resorting to any special techniques.   I will be flying this set up at the Nats so will let you know whether the silencer has behaved itself while flying in competition. @import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

I will be at the Nats and flying - heavens above. BEB, if you want to come and see my Saito to see if the exhaust is still on do drop by the Aerobatics line!@import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

BEB, why couldn't we think big like the Yanks, who held their Nats at their site in Muncie recently? Perhaps an application to the Lottery to buy something approaching the size of Barkston - that might push it into one of the corners of the UK given that such an amount of land in the Midlands might be very expensive. Then again, Muncie is in Indiana - miles from anywhere - OK they still have cheap "gas" in the US - but you could imagine running residential courses (perhaps a mix of camping and low cost accomm e.g. Premier Inn type) to help members to progress. There must be a call for this since there are commercial outlets providing this service now - perhaps a useful additional revenue generator would be for some commercial operators to base there.   Agreed that Barkston Heath has good communications facilities but then the chosen site could also be picked given its proximity to good transport facilities.   It is certainly worth a detailed look now - a credit crunch may prove to be the right time to relieve someone of surplus land. I'm voting YES. @import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

Engine Doctor and Peter Eve - I've done all the things you have suggested to no avail till I tried the 5 min epoxy - which, by the way, Weston UK swear by!   This evening, I had the devil of a job getting the Saito silencer off but nothing like the problem getting the head to pipe joint separated! Managed it eventually, and then fitted the Weston 180 Four stroke big silencer again using 5 min epoxy.   Will let you know how I get on with that once I've flown it. If that doesn't work, then BEB's solution might be the only remaining option! ....and BEB;s just waiting for me to do that so that he can say ...... told you so! @import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

If I may add my tuppence, I think safety is driven by knowledge and procedures. The more you know about the dangers you face with either type of propulsion the more you can develop procedures for managing their risks to an acceptable level. Those who don't take the time to understand what the risks are of operating their engine/motor are a danger not only to themselves but also to the rest of us. Procedures are generally developed in the light of an incident of accident but also because someone has taken the time to think through the risks of operation and how to mitigate them.@import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

Just returned from flying my Saito 180/Capiche. I am delighted to say that after a session of ground running and 3 flights, the silencer remains in place! The only problem is that I have a bigger silencer that I want to replace the standard Saito one with and just hope that I can get the existing one off! I'll let you know how I get on!@import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

I've been practicing for my B ever since I got my A in mid 2002. Lack of time meant that it was only in Nov 10 that I was able to devote the time to learning and perfecting (well sort of perfecting!) the B. It helps if, like me, there are other like minded folk with whom you practice and that the examiner is able to watch your progress and comment on what and how you can do better. That meant that on the day, despite having a stomach full of butterflies, I had sufficient practice under my belt to actually pass the exam.   It has given me a significant jump in confidence as well as improving my flying skills. These have improved even more by entering the aerobatic competition world where again, there is a steep learning curve but lots of people to help you.   I recommend getting a B and at least trying some aerobatic schedule flying as a great way to expand your model flying horizons, skills and, yes, sheer good fun. @import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

BEB, I had sent my Saito off to MacGregors for them to check why it was down on power. It is now back, valve timing, clearances corrected and new piston ring fitted. I decided to use epoxy when fitting the exhaust. I've had an extended ground run, and 2 flights and the thing has stayed in place! Flying again on Friday so will let you know if it is still attached after that.   Peter @import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

Rich   Looked a good landing in the circumstances! Is it meant to make that funny rattling noise? You are a brave chap to fly the aircraft from that field - trees and telephone wires that close must make it interesting! @import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

Hi Olly,   Good one. Have you tried putting the Fly Cam 1 on your Wind S 50? That would be very interesting! @import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

John Olson - you make an interesting point on the weight of the muffler driven by the vibration (and the Saito is a pretty rough engine) lead to the head connnection coming loose. But it would appear that both BEB and I have had the muffler come loose. Now on the standard Saito muffler, the mechanism John refers to would still apply. I have also used a Just Engines (Weston UK made) muffler which is screwed onto the Saito exhaust pipe in a symetric manner i.e. it does not have an offset mounting method. This also came adrift so it is more likely to be the problem of dissimilar metal expansion. As BEB says (stop smirking there BEB!) the only solution appears to be his! Mind you, I have yet to try the epoxy trick that Weston have recommended to me. I'll let you know how I get on with that in due course.@import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

YakMad, that's very interesting. I shall have to see what MacGregors say about the engine shortly. Apparently they have stripped it down and re-assembled it but it is awaiting testing. In what did you have your Saito 180 installed and what was its all up weight? What prop did you use and what sort of vertical performance did you achieve?@import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

Thanks Tim. As a new entrant to this esoteric electrickery, I'm still learning!@import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

I've just got into some large pack size on my new Wind S 110 that uses a Hacker X-80-SB-Pro 3D ESC. This comes with a thin red wire alongside the thick red and black input leads but no instructions on its use. My friend told me that you connect the black leads and then touch the red battery connector with the thin red wire from the ESC. That starts up the ESC without causing any sparking and after the warning tones have sounded you pull the thin red wire out and plug in the thick wire. Provided you are quick, there is no spark. On the occasions that I have been slow, there has been a quite respectable crack! I've no idea what goes on other than there must be some capacitors being filled with charge and the thin wire limits the current flow or else the thin red wire is connected differently from the thick wire. Mind you, these ESCs are not cheap at around £150 a go!@import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

Emma, BEB has posted his solution to this problem together with photos earlier in this thread. You might like to try his solution next.   My Saito continues to be a problem and, as it's short of grunt, I've sent it back to MacGregors to find out if there is a problem with the engine. In the mean time, I've gone the electric route for my aerobatic mount which has given me no trouble, superb vertical performance but no noise - shame, as I'm still an engine man and not a motor man at heart! When I hear whether the Saito is running as best it can or, much better, has been improved, I'll re-mount it in the Capiche and try 5 min epoxy which Weston recommend and see what happens. I'll keep you posted. @import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);