Nick Cripps

DD is building a new model, not modifying an existing one. The CoG (balance point) was used as the datum for the moment calculation. The Laser is 220g (~8oz) heavier than the OS it will replace. Thinking on this a bit more, I would be tempted to err on the side of nose-heavy as balancing that out with a small weight at the rear is much more preferable to adding a lot of weight on what would be a very short nose if in fact it is required.

So the Laser is in fact 50% heavier than the OS. More than I expected , I have to say!

As GG says, as long as you keep the basic dimensions identical, especially the position of the balance point, then you won't see any change in the model's flying characteristics. However, I think your suggested mod is too drastic and you may end up with a tail-heavy model. What you need to do is to ensure that the effect of the weight of the engine times its distance from the balance point (moment) remains the same between the 2 engine installations. If we assume (crudely) that the cg of an engine is on its cylinder centreline and measure the distance from there to the balance point, we can multiply this by the weight of the OS engine to give the "moment" of your existing installation. We then have to calculate the distance we place the Laser from the balance point to give the same moment. We simply do this by dividing the first calculation by the weight of the Laser engine, ie: Laser (distance from BP) = OS (weight) x OS (distance from BP) / Laser (weight) This will give you the distance from the balance point to the cylinder centreline that you will need to place the Laser engine assuming all other things remain unchanged. Give this a try. I'm guessing the answer won't be as much as the proposed 7cm reduction but I'm open to be proved wrong - the maths won't lie!

I took a trip to my local field today to do some D-Day commemorative flights.

Have a look here: Test Standard Guidlines

Great news, Matty 👍

That's a shame, John. Luckily, I decided at the last minute not to bring the caravan up and stay for the weekend but just do the one day tomorrow instead. Now that you've cancelled I'll just have to find something else to do tomorrow before my wife finds extra jobs for me!

Yes, if it has sufficient channels for the model you plan to use it with. Remember that you will need to use one channel for switching modes on the Reflex unit.

Sorry, guys, but I disagree. The simplest approach is to use a standard receiver and wire up the Reflex unit as described in the manual. The system has 3 operating modes and is calibrated for the model. I have found these to work well and, even as an experienced flyer, I find the different modes can be useful at times. You can use it with any receiver including a Spektrum AS3X/SAFE receiver* and do not need to do any further setting of the receiver itself. *If using an AS3X receiver then it needs to have the AS3X switched off. A new receiver straight out of the box will default to no stability and can be used directly. If you remove an AS3X receiver from a different model then you will need to completely reprogram all the settings as they will not be suitable for this particular model. Otherwise just use a basic non-stability receiver such as the AR410 or AR620. If you insist on removing the Reflex unit and want to use the stability function of an AS3X receiver, then you will have to program the gains, etc. yourself via Forward Programming on your transmitter. Oh, and the SBU/PPM MODE cable can be used with receivers that have SBUS or equivalent capability and negate the need for using individual cables for aileron, elevator, rudder etc. between the receiver and Reflex unit. If you don't understand how this works, then I suggest you leave well alone!

Don't think many V2s got as far as Nottinghamshire 🤔 Anyway, I'm sure it will be alright on Monday and you can enjoy your holiday relaxed in the glow of a good job well done 👍

I know how it sounds but it's actually the 1st house on the right-hand side of the main road as you enter the village from the North; the earlier 557 houses don't seem to exist! Let's hope Monday's driver is a bit more concientious.

Parcel Farce apparently attempted delivery this morning but claimed no-one was in. I was at home all day. They also claimed to have left a note to tell me whether to collect the parcel from my Post Office or the local depot. Guess what? No note. I only found this out after checking the tracking number later in the day. I declined redelivery tomorrow (£12 extra!) and collection from the Post Office (£1) so will wait for the next attempt on Monday. This is not the first time this has happened so why does this delivery company consistently fail to find my house when all the others manage it?

Practise on your old cowl first. Also cover the nice paintwork with masking tape so you don't get sticky fingerprints all over it. Don't ask me how I know...

Likewise, Geoff, just a bit further downstream and a good few years later 😉

Finally managed to maiden my Sea Stormer, a David Boddington plan from Aviation Modeller International circa 1993. Here it is at the picturesque Loch Earn where I'm spending the weekend enjoying a waterplane event. 69" wingspan, OS91FS, lovely flyer, as you'd expect from a DB design.

Arrived at Loch Earn this afternoon for a weekend's waterplane flying. Already experienced 3 of the 4 seasons today but managed to get a couple of early flights under my belt while conditions were favourable. Not expecting to see summer anytime soon though.

Excellent. Thank you for sharing that.

I think you're confusing airspeed and groundspeed, a common misconception for learners. A model trimmed for constant airspeed at a constant height and fixed throttle setting will appear to be flying slower into wind and faster downwind, from your stationary position. Whatever you do, don't throttle back on the downwind leg!

Full-size flying boats never seem to scale well to model size, they always appear to have handling problems in the water unless a non-scale step position is used. I don't know why this is, someone with better hydrodynamics knowledge than me could probably tell you! The S6 looks great, would love to see some video of that.

I plan to be there from the Friday afternoon. I'll try not to forget anything this time 😉

Just finished another free-flight model, this time it's a Vic Smeed Tomboy. This was my first attempt at tissue over mylar covering (many thanks to @PatMc for the mylar) with Eze tissue applied using acrylic floor varnish on the wing and some cheap tissue paper on the fuselage. Engine is a Boddo Mills 0.75 Mk2 with Kavan 7x4 prop which should be plenty. First flight will be soon hopefully, once this run of bad weather (must 6 months now!) is finally over.

An amazing achievement, Peter. The first Aeromodeller I bought was in 1974 and contained your article on biplanes for control-line aerobatics. I was fascinated by the subject and must have read it dozens of times and even pencilled in my own design on your sketch showing recommended dimensions. The Duchess published the following month is still on my "to do" list fifty years later! I think an enlarged version for RC would be a great choice for your next design (hint, hint).

DD's link was for Formula Irvine Sport 5 fuel. This is the one you want.

Converting the Tempest kit to produce the Sea Fury seems an absolute no-brainer to me as it would be so easy to do and I'm sure would get plenty of sales so definitely top of the list. Thunderbolt is an interesting idea but not really for me so my vote would go for the Mosquito as the next "new" design. It's about time I had a twin-engined model.

And another at Wollaton Park, on the west side of Nottingham.