Try the DRI, the Red Pig

Somebody built this cartoon scale DR1.
Purportedly, the plans are from the internet.
Chris 'bought' this red model from the builder, at a price so cheap, you know it is a 'give-away', awaiting better home.
Well, Chris fitted his motor, esc and servos and was seen flying it infrequently. He did not like it, understandably so as the short coupled model ought to fly like a pig and cannot be expected to fly consistently, and I am now the owner of the red pig, when the model cannot be repaired anymore, I shall return the motor, esc and 2 servos to Chris.

I figured that the servo arms were awfully short, and this meant short surface horns to get the throws Chris wanted. The rudder horn was broken off the rudder, this is easily fixed with new horns with bigger gluing area. The main concern was the ailerons. Perhaps they worked fine when first built, but now they were too loose and the wire aileron linkages have lots of play. The original aileron servo operates via two push pull wire, attached/hinged to the wire aileron horns with heat-shrink tubing and the 1.5-2mm wire aileron horns runs in 3mm plastic tubing.

This is meant to be a quickie, so I glued on two Hitec HS55 servos for aileron control, bypassing the original linkages. I figured that there is a huge amount of wing area, additional 10gm and drag is nothing in this pig.

I got the model out yesterday, but the wind was too strong for flight trimming. Then at one point, I geared myself to try, but found the rudder horn broke loose. It was no go and I had to retire the pig home. It is fixed subsequently, with globs of epoxy.

The red nose is a discard of a Mig 15, it fits and I think it is good to stay.
If I got the model trimmed out and flying, I think a pig head figurine would look good on this model. And to cover up the two blue servos on top of the wing, how about two big cannon?

Update 1

Over Christmas and New Year period, I have been flying the DRI for maybe 10 times now.
It's like a box, it flies straight and is very stable.
Flying inverted is stable.
The rudder is very effective but I couldn't do nice enough knife-edges.
Rolling circles are ok, in a fashion.
The cowling (without the red nose) is very big and therefore draggy.
The airspeed range is relatively small due to the high drag layout.
I used a 10x4.7" prop and it could almost hover, which means it couldn't.
Yesterday, one of the motor's wire broke from its bullet connector.

Update 2

I soldered back the bullet connector but it does not work. I tried another ESC but the motor would not spin and came to conclude that the motor is damaged. Perhaps I would replace the motor with the FSD motor I used in the Katana. The model would likely be able to fly straight up.

Simplify model construction, MIG 17

The shape of the Mig 17 is a good candidate for simplicity.

The wing is swept back 45degrees. It is easier to draw then the more famous Mig 15 and the planform possesses good moment for the ailerons to act as elevons, I'd say better than a delta. The mid-section's trailing edge is straight. It increases the wing area and is a good location for a carbon fibre strip to keep the span-wise bending moment and torque moment minimal. A carbon fibre strip would increase overall rigidity of the wing.

The horizontal tail area and moment are small and is mounted high on the vertical tail. This is not good, generally, but when the wing's ailerons are elevons, it is of no consequence and presents less drag. The big vertical tail area will point the model straight.

The nose is the air-intake and is short. It is good for mounting a motor upfront. The fuselage, excluding the fin, is short. It is good to reduce needless weight. CG balancing should not be a problem.

Mig 17

1. Simplify the wing shape, forget about the un-pronounced scimitar planform, just straight 45degress swept back leading edge, forget about the minute anhedral, just straight will do, simple flat sheet airfoil.
2. Employ elevons with servos on the wing, flanked by profiled drop tanks/rocket launchers.
3. Flat horizontal tail glued to flat vertical tail and then the entire tail assembly glued to fuselage
4. Blue foam fuselage, hollowed to accept receiver, battery and esc.
5. Blue foam canopy to act as equipment hatch.
6. Using the Turnigy combination, perhaps 18" wing span is good.
7. Chuck and zoom!

Modelling a twin-engined aircraft, OV10A Bronco

Now I have 2 sets of identical motor and esc, how about a quick to build twin motored model?

It has to identifiable as a scale model and one that is easily identifiable by the public. I don't want it to fly in circles and eights, I would prefer it to be more spirited, able to perform mild aerobatics, such as the basic loop, roll and stall-turn. It has to be small and light because the motor is only about 10gm a piece and therefore has to be structurally simple, easy and fast to construct.

A P-38 would be recognisable by majority and OV10A lesser. However, P-38 has dihedral, while it is good for flying especially with the twin rudders, it is more difficult to construct because each boom has to have the wing seat in a handed manner. Also, a P-38 would be rather sizeable if I adopt the scale according to the size of the propeller. An OV10A has no dihedral, meaning the majority of the boom construction is identical, and it has largish propellor. 5" propellor is the largest my motors can handle, 4.5" would be better as tried out in the modified Bug-e fun, the model span of the OV10A would be perhaps around 25". Also, the OV10A has simple slab sided pod and boom (the awkward thing to construct would be the long and bulging canopy), unlike the P-38 which is oval in cross-section, has large rectangular wing and stabiliser, very long nose which is good for CG balancing.

I did a plastic OV10A model when I was a teenager, I chose it then because of its simple lines, perhaps I could do up a RC model now.

OV10A

• Wingspan: approx. 25" (proportioned by 5" propellers)
• 2 x Turnigy 2900kV motor (housed in the booms) and Turnigy 6amps ESC (housed in the pod), running 5x3" propellors, rotating outwards
• 2S 1000mah battery or two 2S 500mah batteries (housed in the pod for CG balancing), requiring to be fabricated, two sets of motor-wire extensions and an appropriate Y connector if both ESCs powered with a 2S 1000mah battery
• One central 9gm servo in the pod for the two ailerons
• One 9gm servo for the elevator in one of the boom, curved upwards to the elevator, substitute the control horn with an ez-connector.
• One Hitec micro receiver in the pod
• Wing constructed of 1/16" curved balsa sheet with exposed stiffeners at the bottom and a continuous thin carbon fibre strip glued under the leading edge for increased durability. Ailerons are hinged and activated ate via long aileron arms all the way to the central pod.
• Alternative wing would be more built up, it would be sheeted fully at the top and at the bottom from boom to boom at least.
• No flap-control. It seems a great feature and should be simple to construct, but let's keep it off.
• Stabilisers constructed of 3/32" or 1/8" flat sheet
• Pod constructed of 2 pieces of 1" thick blue foam, maybe I will make it knock-offable.
• Alternate pod would be balsa sides and bottom, blue foam pod nose and tail pieces.
• Canopy is a carved and sanded blue foam piece, attached to the pod magnetically for easy access to the battery/batteries, ESCs and receiver.
• A more attractive alternative canopy/cockpit, but which involves more work, is to form a clear canopy. Simple push moulding is out because of the bulging shape of the canopy, a more practical approach would be to carve a male mould from blue foam, and shrink a clear bottle over it. With the pod constructed, balsa sheet will be used for the two bulkheads and canopy/cockpit floor. This underlying frame is then fitted out with dashboards, headrest etc and painted and the two pilot figurines installed. Then the shrunken plastic piece is glued to the underlying frame and the excess plastic trimmed. The canopy is then taped for the canopy frame and the whole assembly magnetically mounted onto the pod. The canopy is a prominent feature of the OV10A, a solid blue foam piece while dimensionally accurate would not be able to create much interest.
• Booms constructed of 1/16" balsa sheet, with bottom access (hinged and taped) to swap motor wires.
• No rudder-control. I would like to have control over the twin rudders, but to maintain simplicity and keep the weight down, I may have to forego this. If there is going to be rudder-control, I would use 2 x 5gm servos housed in the booms and connected through a Y to the receiver at the pod.
• The pod and booms could have 3mm aluminium tubes glued in to receive the removable undercarriage, made from 1.5mm piano wire, friction fitted into the tubes.
• Hinged with Guardian's surgical tape or narrow pieces of filament tape, covered with tracing paper (bottom of wing shall be bare), white glue coated, sprayed basic colours, unless I can find suitable coloured film to iron on, which is the preferred choice for lightness.

Food in the airport terminal is expensive

Food and drinks in airport terminals are expensive.
If you have to eat and drink, you pay 2-3 times more than you would outside.
The solution is to choose Fast food. This morning I ate at Subways. It is not what I would normally have for breakfast, but I don't loathe it , so I had the $5 combo.

Maybe these Fast food chain has to maintain contact with their customers, and they don't feel comfortable to increase their prices.
If I was to ask Killiney or food court operators, they would probably say the price is higher because of higher rental and their employees have to travel far. These reasons apply to Subways, MacDonald, Burger King and the like.

The main differences between Krisflyer Gold and Silver/non-member

1. Silver does not have access to the lounge. The sofas, papers, food and drinks. Nobody really watches the TV, quite a few uses the wifi.
2. Silver joins the common queue for boarding pass. Easily double the time to check in.

Point 2 is, on reflection, interesting.
It is not as if Gold staff works faster or we don't have to queue.

Can we interpret that the common queue needs more checking in staff?
Is there a conscious act of limiting and inconveniencing to augment the image of the Gold class?

Modified Bug e-fun flies

Some 1/16" balsa sheet is used for ailerons,  elevator and rudder. All control surfaces are hinged with surgical tape from Guardian. 1-1.5mm pushrods are Z-bend at the servos (because I don't want to enlarge the servo arms' holes), accorded adjustability with EZ connectors from GWS on control horns that have the holes drilled larger (to 2.5mm diameter) to accomodate the connectors (both from HobbyKing, the horns were not what I ordered but are usable).

Servos are 9gm for ailerons with two push-pulls, and 5gm for rudder and elevator, mounted in a single file on the top of the model, superglue in placed. In future, I shall not use the 5gm servos that I bought from Jethobby. These 5gms were intended for Mini-Popwing but which I didn't use them because they stalled too easily. I installed them on this bug e-fun but they stalled occassionally. These 5gms servos are too weak.

The Turnigy 1806motor and 6A ESC (both from HobbyKing) and a GWS 5x3 propellor provides ample thrust. The motor is mounted with its radial mount (I deem the motor shaft too short for direct grip with nylon ties) on a 2mm ply-faced 1/4" balsa firewall with 2mm socket bolts and blindnuts (the radial mount and firewall probably weighs as much as the motor itself). The firewall is first glued to a 2mm carbon fibre rod pylon. As the throttle increases, the whole motor rotates downwards, giving more downthrust. Interesting to have variable downthrust but not a good idea for reliability. The rod was then replaced with a 5x1mm carbon fibre strip. No more variable downthrust but it snapped when crashed. Finally, the firewall was just epoxied onto the nose.

With Hitec receiver in the canopy region, and a 450mah battery (bought from Rotor Hobby, tagged as 500mah) push fitted in a slot below the wing, the model flies good. There must not be too strong of a gusty wind.

It flew ok. Rolls, loops, inverted are ok but not straight and true. Stall turns are iffy with the smallish rudder and I got about 10 minutes of flight time. Maybe it is the Turnigy 6A ESC, it is warm even at zero throttle and I didn't have this symptom with the Turnigy 10A ESC. Anyway, 10minutes is good enough, I like the smallness of the 6A ESC and will use them, but next time, I shan't use the 5gm servos, I shall use the 9gm servos like Hitec's HS 55.

This experiment was done to evaluate how the 1806 10gm motor feels. I find this airborne package ok, although the 6A ESC was warm and the 5gm servos quite useless.

Now that I have an idea of what it can deliver, I can do up more interesting models using them.

How about a scalish Gee Bee Model D Sportster or since I have two of this motor and esc, a scalish twin of some sort? Short-nosed subjects like the Sopwiths are still out of bounds until I can figure out how to concentrate the weight to the nose which currently. Maybe I will find reliable 5gm or sub-5gm servos one day.

Update 16/12/2013
My two Mini-Popwings are down. One with a motor wire pulled out of the connector and the other a jittery servo. I am left with the mini piper cub and the Bug e-fun. For 'challenge', I flew the Bug e-fun yesterday.

I flew 6 batteries, during these flights I added 10gm of lead to the tail. The model was nose-heavy to start with.

The flight times of flying freely with full use of throttle and conservatively with gliding time was not of appreciable difference. The batteries lasted about 9 minutes for both forms of flying. I thought it would either be the ESC or that I have over-propped the motor with a GWS 5x3. I swapped in a 12A Hobbywing's for one flight. It seemed slightly more spirited, but the flight time was similar. Perhaps the 2900kV was overworked and hence drawing more amp while the propeller flips over at less than 90% of the 2900kV. I tried a GWS 4.5x4. This is better.

I could do rolling circles with this model. The rudder is however too small and the rolling circles relied on elevator input instead. Perhaps if the rudder is bigger the model might have a chance of doing knife-edge. (I doubt it, but still, it is plausible)