Straight Up's blog View Details
Posted by Straight Up | Jan 09, 2017 @ 02:28 AM | 5,585 Views
Background (skip this if “TLDR”)
When I first learned to fly RC in 1990, the local magazine Airborne (Australia) featured adverts from Trimair, a “jet” manufacturing outfit. Back then there were no turbines and electric power was all brushed motors + NiCd batteries, so flying was all I.C. The Trimair Spectre looked incredible and my flying buddies and I all lusted after it. Designed by Tony Roessen using the Northrop F20 as a design basis, it was the ultimate sport jet of its time, arguably ahead of its time. It was designed around the newly released OS 0.91 VRDF, and using Tony’s own-designed and marketed Ramtec ducted fan; it was a formidable piece of machinery. I was desperate to become proficient enough to fly such a jet, and worked my way into pattern aerobatics and pylon racing. However, jets were EXPENSIVE and the $500 kit price tag + all the additional gear pointed at a $2000 plane, which was well outside my reach. We’re talking 1990s money!

The unreachable cost slowly changed when I graduated as an engineer in 1995 and joined the workforce. I was now a proficient flyer, and I could see the end goal. In 2001 I was awarded a large bonus from work, and stipulated with my partner that $2000 would be reserved for my Trim Air Spectre. I placed the order, complete with Spring Air retracts, K&B 1.00 engine, tuned pipe, Ramtec fan and a lot of other goodies. It all arrived in a coffin-sized box, to my utter delight.

However, my wedding was on the horizon,...Continue Reading
Posted by Straight Up | Apr 03, 2016 @ 10:42 PM | 7,552 Views
I absolutely love jets. I enjoy flying all types of planes, from pattern aerobatic to pylon to glider, but jets are my absolute favorite. They're inefficient, heavy and tricky to fly... and I still love them. I've been trying to get a reliable "full house" jet (complete with retractable landing gear) for years, achieved last year when I picked-up the awesome Freewing Stinger 90. However, a composite jet is the dream, and was realized on the weekend when I maidened my Hobby King Diablo.

The maiden was delayed by a month due to the Change Sun fan exploding - in its defense I overloaded it. The damage to the fuselage was enough to warrant some repairs which have come out pretty well - just need to do some touch-up painting now. It had to fly first to prove the repairs were warranted.

I have a Ramtec EDF in a different jet which is all nylon and it happily churns at ~7kW input, but I just don't trust the Chinese plastic fans anymore after the CS fan's demise. Therefore I replaced it with an all-alloy fan system:
- Alloy DPS Series 90mm 12-Blade EDF Unit with Heatsink
- Dr. Mad Thrust 90mm Cast Aluminum Alloy Rotor
No issues with this beast! It's happily turning on 8S Turnigy 5000mAh 3S 40C Lipo Packs (3S + 3S + 2S) using a Turnigy SK 1500Kv motor at ~125A / ~3600W. The AeroStar Advance 150A ESC Opto handled all that current and power without an issue.

I fly from an unprepared field with grass control being conducted by the resident sheep. The...Continue Reading
Posted by Straight Up | May 25, 2014 @ 09:51 AM | 13,954 Views
I've been in the hobby since I could walk, but I only got into helis back in 2006 when I moved to Saudi Arabia. I wasn't particularly interested and thought helis looked like more trouble than they were worth, but The Align T-Rex 450 kit could be transported in my luggage and fly without a runway – perfect for my RC fix until my planes arrived! I spent 3 hours each day practicing on the simulator, and was ready to fly the bird after 2 weeks. I surprised myself by coming to grips with heli flying relatively quickly, and was even more surprised to find out I enjoyed it so much. What a rush!

My wife encouraged me to get a T-Rex 600 soon after, having seen me fiddle on the bench with the diminutive 450. However, I shunned the much higher cost and also wondered what a 600 could do that my 450 couldn't. A few years later Hobby King brought out the HK-600GT – a clone of the T-Rex, but all “blinged” out with alloy fittings and carbon frames, right out of the box! At $140 I figured “I have to try it out” – this was cheaper than my original PLASTIC T-Rex 450 kit!

I ordered the kit in late 2012. So why such a late blog entry? I had to be sure that the resultant set-up was reliable. I’m happy to report that it is... now. This is an incredibly good heli. As good as the T-Rex 600E, but at a much lower cost. However, there are some items to change from stock. I show a flight video at the end, and the most frequent question I...Continue Reading
Posted by Straight Up | Mar 09, 2013 @ 10:13 AM | 14,147 Views
I'm not really into sport planes, but I realised my fleet was all a bit extreme. EDF jets, pylon racers, CCPM helis and pattern planes. I needed a simple plane to just go fly and cruise around. I love flying my Dad's "Sticks", but they lack visual appeal. I spotted the Piper Cherokee on Hobby King and fell in love with its sleek lines and simple lay-out. A worthy sport plane, perhaps? At just over 100 bucks it was worth a shot.

The "kit" (ARF) arrived without damage, and everything was beautifully built and covered. The engineering was mainly good, with some excellent innovative features. I was very happy to see all the servos near their respective control surfaces. I just don't subscribe to the idea that we need to locate the servos amidships anymore, with lengthy mechanical transfer systems to get the servo motion to the control surface. I'd rather run small, flexible electrical wiring than rigid pushrods around a plane! Most impressively, the rudder and elevator servos were located internally under a hatch in the tail, with concealed pushrods - very neat yet functional. In fact, the only visible pushrods were for the ailerons, as even the flap servos and their pushrods were fully concealed. I was surprised to see the flap servos were not screwed in place, but instead "sandwiched" between ply mounts. I used some wraps of masking tape around each flap servo to hold them securely in their squeeze mounts. The only control item I...Continue Reading
Posted by Straight Up | Mar 08, 2013 @ 06:41 AM | 7,567 Views
How not to bungee launch a mini jet:
Hobby King T-45 50mm EDF - roll during Bungee launch (0 min 18 sec)

Posted by Straight Up | Feb 18, 2013 @ 10:50 AM | 15,253 Views
While flipping through a hobby mag I saw an advert for the Sig Rascal 72EG, and fell in love with it. However, at $310 plus scary shipping to Australia it was a no go. Luckily I found a similar plane in the Aviator Pro .60 ARF from Value Hobby, and fell for it too. Sadly Value Hobby won't ship outside the Lower 48 (despite a colossal population outside that boundary!). I arranged for a US shipping agent and managed to acquire the Aviator Pro 60. Cost me $160 to ship it to Australia, so you can imagine how much I wanted this plane (still cheaper than a Rascal 72EG).

Very impressed with the build quality. I was absolutely amazed to find the wing bolts all pre-fitted and lined up perfectly! I didn't need to measure, drill or fit the blind nuts - nice! The wing fitted so well I simply bolted it into place. I never glued my wings together. I switched out the front nylon wing pegs for carbon fiber, not because of any concerns about strength, but because my pegs were a bit short. Other than that, the build was stock-standard, although I mounted my tail servos right down the back end - see below.

Achieving correct CG with a big battery up front
Many complained about having CG trouble when mounting the battery in the nose causing an overly forward CG, but I didn't have this issue. I fitted servos in the tail - one per surface. That is, one servo for each elevator and also a rudder servo. I used digital micro servos, and the three are still considerably lighter...Continue Reading
Posted by Straight Up | Apr 22, 2012 @ 09:07 AM | 9,645 Views
A few months ago I was lucky enough to pick-up first place in the prize draw, and scored a $500 voucher from Tower Hobbies. One of Tower's planes caught my eye: the Top Flite P-51D Mustang 60 ARF. I've never owned a warbird, and this would be a serious step into that camp! This one is definitely not a park flyer!

Despite being an ARF, the build was not straightforward, and took more than the standard "week of evenings". The plane was intended for glow power, and built in the traditional way - i.e. servos and gear all in the mid section of the plane. If I had followed the intended layout it would have needed half a pound of lead in the tail to hit the recommended CG! So some re-engineering was required, focusing on getting all gear as far aft as possible. Hobby King came through with the power system:
  • Motor: Turnigy Aerodrive SK3 - 5065-320kv
  • ESC: Turnigy dlux 120A HV Brushless Speed Control
  • Batteries: Rhino 8S (4S x2) 3700mAh 30C
  • Prop: Turnigy Ultra-light wood propeller 15x10

The specified weight was 9 -10lb (4.0 - 4.5kg) and I was shooting for a power loading of ~500W/kg (230W/lb) - that nuclear power loading I'm so fond of ("F3A Pattern" setting in EAS) that enables my planes to fly in any direction I choose at my nominated speed, including plumb vertical. This translated into a target power of 2000W. It would be grossly overpowered, but only at full throttle. Therefore it should cruise very...Continue Reading
Posted by Straight Up | Jun 04, 2011 @ 09:57 AM | 12,420 Views
I am blessed to have such a supportive wife. With our son barely a month from birth, I got a hankering for the glider I'd always wanted. It was a crazy time to consider getting a new plane, and a plane like this was never going to be cheap, even with Uncle Hobby King supplying the electronics at rock-bottom prices. I spied the plane in a Brit Magazine, going by the name "Elegant", made by RCM Pelikan. A fully moulded fuselage, tee-tail, massive 2800mm wingspan, ailerons, flaps, and a really sleek look! The trouble was, the distribution company in the Czech Republic had sold out of all stock. A mammoth internet search ensued, with over 20 inquiries to places as far afield as Sweden. Most companies didn't even respond. Some companies had it, but wouldn't ship it to me. I came across a company in Spain who went above and beyond the call of duty, and worked tirelessly until they found me a semi-reasonable shipping deal, which was still exorbitant. The kit was going to set me back about $300, and the shipping was a further $200 (!!!). At this point I contacted the British distributor (whose advert in the magazine started all this) and asked them "what the heck? The colour of my money is different!?!?". I gave them a "no liability" clause, and asked what they could do. They agreed to ship me the plane, despite their UK-only shipping policy, and cut the total bill to $350. I wired an additional $30 to the Spanish company for their...Continue Reading
Posted by Straight Up | Mar 09, 2011 @ 06:35 AM | 11,519 Views
Alas the Canadian experience came to an end last June. It was awesome - from the surreal experience of genuine snow, to the vivid summer green, to the amazing Fall colours. An experience to be savoured. Now it's back to 100'F, olive coloured leaves and yellow grass. However, the sky is nearly always blue and we fly all year... but I flew year-round in Canada too!

First New Plane – Hobby King Sniper Pushy Cat EP
I ordered a Sniper Pushy Cat EP from Hobby King to "tie me over" while I waited for my gear to be shipped from Toronto. What a beauty! I built it initially as a belly-lander, with the intent of fitting retracts later. I fitted a 400W Hobby King motor and 2200mAh 3S Lipo for serious motivation. The first launch was a complete disaster - not enough airspeed, so it tip-stalled in and rekitted itself!

Luckily I only busted one of the tail booms. I don't know how I got so lucky. The ground is HARD here! I glued it back together and had my buddy and ace-flyer Kristian launch for me on the next attempt. He was a bit freaked by the prop, and everyone gasped as it tip-stalled again... but this time Kristian's firmer throw and my thumbs starting on the sticks meant I caught it. It flew very well after the initial launch, and trimmed easily into wide, fast circuits. After a smooth belly landing Kristian commented “nice plane, but it needs wheels!”

After this “proof of airframe” flight, I stripped it down and fitted Hobby King pneumatic...Continue Reading
Posted by Straight Up | Jan 24, 2010 @ 01:04 PM | 10,139 Views
The snowy winters of Canada and a chance find of Dubro aircraft skis at a hobby shop in Buffalo (where they get 9 feet of snow per year!!!) motivated me to finally fit skis to one of my planes. My little park flyer Hyperion Helios had its conventional wheels removed, and the skis fitted within an evening.

I was very concerned about how this would all work. The skis are relatively small, so I feared that even a foot-print in the snow would cause them to dig in, potentially ripping out the undercarriage. My fears were unfounded - the skis float over pot-holes, punch through snow mounds, and are totally at ease in bumpy terrain. The plane actually lands and taxis around easier than when it used wheels! Due to the reduced drag (compared with wheels on grass) the take-off run is barely 3 feet, and the landing roll out (slide out?) is short too. The plane works better with skis!

In flight I didn't notice any major trim change, except when one of the ski mounting bolts came loose in flight and the ski swivelled to a vertical position. The plane began to dive and required a lot of up elevator to maintain height. I was very concerned that the ski would dig-in on landing, but as the skis touched down, the faulty ski spun horizontal and the plane taxied back, with no indication there was ever a problem. The loose bolt was tightened and lock-tited to ensure that scare didn't happen again!

Another great dimension to flying! I just wish the snow was still here for more ski flying!
Posted by Straight Up | May 08, 2009 @ 10:31 PM | 11,787 Views
A project that took far too long finally achieved a milestone today - maiden flight! So this isn't the end of the project? No, retracts will be installed next.

The kit was extremely well travelled. Manufactured in China, sold in the USA, shipped to me in Saudi Arabia, impounded by Saudi Arabian customs, shipped to my parents in Australia, then I moved from Saudi and had my parents send it to me... in Canada. Whew! It took a year just to finally get my hands on it!

As for the build, I was never happy with the built-in incidence that was obvious from the outset. Wing leading edge 10mm from base of plane, TE just 1mm, and horizontal stab set at 0-0 just behind it. I know this works - many people in this forum have shown it works, but there's no doubt about it that this will create variable trim as the plane's speed changes. A slightly forward CG counteracts this trim and gives everyone that warm fuzzy feeling of stability... until they roll inverted.

I adjusted the wing incidence to be 0-0 with the horizontal stab - i.e. raised the trailing edge on both wings until LE and TE were at the same "height" from the bottom of the fuselage. Now there would be no inherent down-force from the tail, so I opted for a more aft CG, starting at 70mm (I can sense you all cringing right now - relax!).

Everything else was pretty-much as per the Carl Tulenko build (that really helped a lot, especially for the fan assembly). However, with retracts planned I dropped...Continue Reading
Posted by Straight Up | Aug 02, 2008 @ 11:35 AM | 11,799 Views
My previous blog entry about Canadian flying gives details about flying my Passer-X Warmliner / powered glider. A few months ago after a great flying session from a local park (with due respect for the safety of others), a couple of mid-teen "kids" approached me. They had been watching it fly and asked to know more. I explained that it wasn't a toy, but a high performance glider. They were impressed with the way it flew, and were shocked at its size - they didn't realise it was "so big" until they got close!

One of them stepped forward, introducing himself as Nikhil, and explained he'd like to become an RC pilot. He had an "Airhog" plane back at home that was a total failure, so he hoped I could show him the right way. I was a bit sceptical, since I get a lot of these inquiries, but I promised to email him some further details. I also warned him that the cost would be a fair bit more than an Airhog - this was a relatively expensive hobby.

I emailed Nikhil a suggested set-up for a beginner - a Great Planes Fling 2m thermal glider, complete with 4-channel radio and hi-start. I had already flown the Fling HLG and knew that Flings were not only quick+easy to build, but excellent flyers. I explained that this aircraft would be relatively simple to control so he would progress quickly, but also offer challenging flight performance, and easy launching. It was about the cheapest set-up I could advise, so his financial risk was minimised....Continue Reading
Posted by Straight Up | Apr 12, 2008 @ 08:24 PM | 13,732 Views
I left Saudi Arabia late last year, right on the back of a burning hot summer. I found myself in Mississauga, Ontario, Canada, with a whole lot more access and freedom obtaining model aircraft gear, but a winter that was the diametric opposite of Saudi! Suddenly I would be concerned with overcooling, rather than overheating !

I sold all my gear in Saudi, an initiative encouraged by the Saudi club due to import restrictions. Time to renew the fleet! First requirement was a new T-Rex 450 - I got the new V2. It never ceases to amaze me how convenient choppers are to fly. All you need is enough room to take-off (about 4sq.ft) and some clear airspace, and you can fly. With Mississauga immersed in snow and ice, the fixed wings would have to wait.

I flew the T-Rex out of a local park, in surroundings like I'd only seen in movies. What an incredibly beautiful place. However, the snow was deceptive, and I discovered the HARD way that hard ice lay beneath. While walking out into the park, Tx in one hand and T-Rex in the other, I slipped flat onto my back, winding myself. All I could think was "what's happened to my gear!!!!?!?!?!?!?"

My wife (the photographer) was repeatedly asking me if I was okay, and all I could get out was a muffled and grimacing "how's.... my.... chopper...???...???"

Luckily I'd launched the chopper along the ground on its skids just as I fell back, and my Tx was safely on my tummy. A painful start to the...Continue Reading
Posted by Straight Up | Aug 30, 2007 @ 02:01 PM | 11,085 Views
I built an E-Flite Brio 10 a few months ago, and was a little disappointed by the power train's performance (not a fault with the aircraft). The Hacker A30-16M motor was OK, but I ended up wringing every last watt out of it and even then I found myself reaching for more power (e.g. following a vertical snap sequence). Everything about my flying craves unlimited vertical, and not just chugging slowly, but a spirited zoom to altitude. The Hacker just couldn't deliver this, even at 36A / 360W. Don't get me wrong - it was good, and the vertical was unlimited, but it was slow and didn't look convincing. My ST90 [over]powered Extra 300 was much more convincing. I suspect that flying in 100+ºF temps didn't help - low air density, and additional major heat load for the electronics.

I've read about Brios being powered by E-Flite's Park 450 motor in a lightweight set-up, which I'm sure many would advocate, but I went the other way. An E-Flite Power 10 outrunner would have been a good start, but I thought "let's not do this by halves". I set about specifying a system that would deliver serious watts when called, which is exactly how I like to set-up my planes. I selected the Hextronic 35-42C 1000kV motor, which is rated to 600W, a Hobby-Wing Pentium 60 ESC, and a Hextronic 4S2P 2600mAh Lipo. I could have used a 4S1P battery, but the 2P option allowed me to assemble a pack that would fit the plane better (4S1P packs tend to be very long). I also installed a Corona Rx...Continue Reading
Posted by Straight Up | Jul 07, 2007 @ 01:31 PM | 10,995 Views
Some pics of my RC life. I just wish I had some digi pics of my earlier models. One day....Continue Reading
Posted by Straight Up | Jul 06, 2007 @ 11:57 AM | 11,288 Views
I have been building and flying model aircraft since I was 4 years old, but I only got into R/C when I was 15. I flew control-liners in my younger years, and also free-flight gliders + rubber-power. This was a good grounding in building and flight principles.

Memorable Moment
I built a Veron Cardinal free-flighter when I was 14, using plans from a kit my dad had recently built. I powered it with a Cox Baby Bee 0.049, and it flew WELL. The motor was way too powerful, sending it in a vertical spiral to about 1500ft , then it began a slow circling glide. I lost it on its first outing, being unable to keep up despite running flat-out down-wind. Thankfully I put a return-to-sender message inside, and received the phone call soon after I got home. I later switched the motor to a Cox Pee Wee 0.020, only to lose it AGAIN . Another phone-call and another reward payment later, my folks agreed it would be cheaper to get RC gear.

Going RC
My first RC model was a Cosmo 25SR, shouder-wing trainer, powered by a Magnum 25 2-stroke. I had completed some stick-time on my instructor's Ugly Stick, which scared the heck out of me . The Cosmo was a good plane - very neutral to the controls, and taught me a lot. I got over-confident after a few weeks of training, and performed a loop at low altitude. I came out even lower - into the ground! . My instructor was not impressed, and even though the damage was minor, this set-back my learning a LONG way. I eventually went solo many...Continue Reading