Twenty-eight Alto aircraft, forty-seven aircraft in total, almost a hundred visitors. New metallic Alto NG accompanied by a tail dragger Alto TW. That is a short summary of 1st ALTO FLY-IN, that Direct Fly hosted on a third Saturday in May 2023 at Medlánky Airfield.
Fly ins started shortly after 9AM. Weather across the Czech Republic was changing throughout the day, that’s why the opening ceremony moved to half past ten. Nevertheless weather in Medlánky was beautiful for the rest of the day, so most of the visitors ended the day with sun kissed cheeks.
After the company’s CEO welcomed all quests, synchronized flight exhibition of Alto NG and STOL Cruiser took place right above the quests’ heads. Following walk through production with presentation of riveting and avionics installation was a huge success. Instead of the half an hour that the tour was planned to last, it took three times that long with their interesting questions, basically till they realised they were hungry. Very welcomed lunch was provided by local brewery.
After that the new high wing STOL Cruiser was introduced by the engineer who has been a part of this project since it was just an idea. A look in the future was followed by the company’s owner reminiscing about the beginnings of Direct Fly and its most successful aircraft Alto.
The event was attended not only by Czech aviation enthusiasts but by visitors from Poland and Turkey as well. For the first time in history Zongshen engines were introduced in the Czech Republic by ZAEC company.
Many thanks to those who attended the first edition of our Alto Fly In. We hope that after such a great beginning it will become a very successful tradition.
In past few days we received information about a number of phishing e-mails that are aiming to steal sensitive information from our customers and colleagues under Direct Fly’s name.
Please always check sender’s e-mail address. Always think about what you’re clicking on. Always check URL adress in a link.
Contact us on marketing@directfly.cz in case of any uncertainties or suspicious activities and messages.
Even pilots in Australia are carefully observing our developments with the STOL Cruiser project. Short article has beeen published in an online version of a local Sport Pilot magazine about the newly designed aircraft and its flight tests. Australia seems to be an ideal market for STOL type aircraft. Aircraft that are able to take-off and land on a short and unpaved surfaces. Also for this category the atypically high cruise speed and flight performance of STOL Cruiser is well appreciated added value for a comfortable traveling on longer distances.
You can read the whole article in the link below:
Since 2018 Direct Fly supplies light sport aircraft Alto to Australia. Seventh piece is on its way to Melbourne’s port to our colleagues from AeroEdge Australia right this moment.
Last couple days, whenever the weather allows, we fly and test the new aircraft intensively.
Flight performance and characteristics are really positive so far. We were pleased by stall and cruise speed, as well as by take-off distance and climb rate. For a tail dragger the view from the cockpit is excellent, both on the ground as well as during flight. The cabin is also huge for this category.
We will gradually test other flight configurations and evaluate results of flight tests. Based on that additional adjustments and improvements can be designed and made and data refined for following strength tests.
STOL Cruiser is developed in cooperation with Czech Technical University in Prague. This project was co-financed with state support of Technology Agency of the Czech Republic in EPSILON programme.
The annual meeting of ultralight aircraft owners and producers took place last August weekend at Jihlava airfield. Despite quite a bad weather in Brno, we were able to fly in with two Alto’s from Medlánky airfield. In total there were nine Alto aircraft present in Jihlava. We were also happy to present our new Alto NG in flight and towing gliders.
Many thanks to Light aircraft association of the Czech Republic for organizing a pleasent event and to our dear customers for building such a great Alto community.
The outcome of the new Czech certification UL-2 MTOW 600 kg together with more than fifteen years of experience with production and operation of Alto aircraft. Good flight qualities and stalling characteristics, known from previous Alto model, in combination with improvements and modernization. Complying with the latest ASTM LSA standards.
That is the new Alto NG.
The most visible change in comparison to the previous Alto model is the length and shape of engine cover. With a ten centimetre longer cover the Alto has a more elegant look with smoother transition between the fuselage and cabin. However, this change is not only about the visual improvements, but with related lengthening of engine bed the engine has been moved forward. That is why the Alto will no longer fall on its tail while its pilot is getting into the aircraft. This change also allowed to use the full capacity of baggage compartment, which is 15 kgs.
New engine installations
The new aircraft introduces a better solution to engine and oil cooling as well as to cabin heating and engine overcooling in winter months. All of this thanks to the new shape of engine cover and its inner structure – carburettors air intake and cylinder baffle. New airbox stabilizes the air between both carburettors better than with previous model, which helps with calmer engine run and the ram air inflow provides enough air for the otherwise standardly not super-charged engine. In cooperation with water and oil thermostat, and the choice between three sizes of oil coolants, the engine is neither overheated during climb nor overcooled during descent.
Reinforced Alto
Based on our experience with periodical check-ups and service we came up with a new attachment of the newly reinforced front leg in engine bulkhead with rivets of greater load capacity. We also stiffened shoulder strap fixings inside the cabin.
Even though the wing looks the same at first glance, there has been reinforcements, changes in construction and simplification in production. Small collisions that complicated flaps installation have been removed as well. New pitot tube location has been established and airspeed meter calibration has been tested in flight with Garmin and Dynon probes.
On the fuselage, in the upper part of the skin and under the windows, new longerons were added to increase the stability of the skin. Czech certification calculations showed the need to increase the VD speed from 270 km/h to 295 km/h. In relation to that the control stiffness had to be increased and the centre of gravity of the elevator had to be moved closer to the rotation axis. This was achieved by elevator tips mass balance, which also contributed to reduction of control stick force during taxiing, better force response during manoeuvres and better trim ability in various landing configurations.
Flight control change
With the new Alto NG control stiffness has been increased by flight control concept change, from control stick to control surface. Cables for pitch control have been replaced by system of pull rods, levers and rockers, which brought faster and more precise aircraft control with quick response to the pilot. There is also no need for turnbuckles wiring and ropes tightening. The cables remained used only for rudder control. This change meant a long list of construction adjustments – stiffening, rocking arm holders, inspection holes etc., which are visible from the lower side of the fuselage, mainly under the baggage compartment. The whole control system is connected by fitted bolts with cotter pins.
Secondary system of pitch trim control
Another important change was adding second trim tab on horizontal tail surface. According to the new regulations, the aircraft needs to be trimmable in a certain range of speeds in given configuration in the worst possible centre of gravity position. In reality that means that it is necessary to fulfil the 1,1 times stalling speed with fully extended flaps with maximal forward centre of gravity. Our solution was to develop our own flap controller, which controls the second trim tab (on the right side of horizontal stabilizer) at the same time. Increasing flap deflection, deflects the second trim tab and decreases the control force for pilot. This force never really goes away, so that the pilot knows about the simultaneous change of flaps deflection and wing pitching moment. However, the pilot can control the trim on the left side of horizontal stabilizer by himself the whole time and can trim as required. For full aircraft trimming in longitudinal direction a second trim tab on the right side of is used, which is controlled from the cockpit.
New possibilities
Beside the construction changes Alto NG also brings wider selection of accessories and additional equipment. There is a new option to choose an in-flight adjustable hydraulic propeller. With this type of propeller, the aircraft has a great flight performance, both in ascension and in cruise mode. This will be appreciated mainly by those who occasionally use Alto as a towing aircraft. In comparison to the electric propeller, the hydraulic one has a perfect and almost immediate control over the propeller regime.
In the interior, there are new seats with headrests available. We also adjusted the ergonomics of pedals and control sticks. In addition to standard headset holders behind pilots’ heads, connector sockets have been placed in between passengers. Lemo connectors are an option as well.
In the interior, there is also the already mentioned new flap controller and a fuel valve with START button, where it’s mechanically impossible to start the engine with closed fuel valve. There is no need to think from which tank it is necessary to pump the fuel first when both tanks are full. It is now possible to pump from whichever tank the pilot chooses because the unused fuel returns to the tank, they’re pumping from.
Even with the new model we did not stop designing instrument panels for each customer specifically, based on their preferences and wishes. Thanks to many years of experience we are able to suggest the right choice and combination also in accordance to customers financials.
Alto NG in the most luxurious and complex specification can be produced with empty weight of 356 kilograms, Alto NG with fixed propeller, basic flight and engine instruments and without parachute rescue system can be produced with empty weight of 320 kgs.
The whole certification process has been a huge experience for us. We would like to thank all of our customers for their patience and understanding that they continued to have with us even in times of global pandemic. We believe that our aircraft will pay you back.
Last but not least, development at Direct Fly won’t stop with this certification. In the future, we would like to create uniform design of aerodynamical wheel covers, optimize shape of vertical stabilizer, design adjustable pedals and seats and re-design the instrument panel to allow installation of more flight and engine instruments.
New LSA prototype was introduced for the first time this week at International Engineering Fair. STOL Cruiser is a new aircraft developed by Direct Fly in cooperation with Department of Aerospace Engineering, Faculty of Mechanical Engineering CTU in Prague.
STOL Cruiser was designed as an all-metal, single engine, two seat, high wing aircraft with conventional empennage layout. Powered by propeller power unit in tractor configuration. It’s main advantage is a very short take-off and landing distance mostly thanks to low stalling speed. The aircraft advantage is also its high cruising speed unusual for this category. Significant asset of this aircraft is also a big cabin space which enables the aircraft for multipurpose use. Fuel tanks with maximum capacity of 100 l guarantee relatively high range and endurance
Wing of the aircraft is self-supporting and trapezoidal. Trailing edge is equipped with efficient Fowler flap which is divided into two parts. Leading edge is equipped with a slat. Inner part is controlled together with flaps while outer part is automatic and opens when certain angle of attack is exceeded. The fuselage has semi-monocoque construction built by a load bearing skin, bent stringers and pressed bulkheads.
Another target of the project has been a development of Match Hole technology. The principle of it lies in drilling holes for the connecting material already in the stage of metal cutting – milling process. The parts thus obtained are then passed on to other shaping operations – bending and forming. After the subsequent surface treatment, the parts are passed on to final assembly. The system ensures that the individual parts fit together with a minimum of finishing operations. The main advantage of this system lies in its effectiveness. Implementation of MHT drastically reduces production costs and times, eliminates the need to use complex tools/jigs to mount individual parts in assemblies and reduces the need for experienced personnel.
World premiere for STOL Cruiser aircraft is planned for international air show Aero Friedrichshaffen in April 2022. Certification flight tests of the aircraft will take place in Spring next year as well.
This project has been co-financed with state support of Technology Agency of the Czech Republic in EPSILON programme.
Are you in Denmark, Sweden or Norway? Do you want to see our Alto 912 TG in person without having to travel to the Czech Republic? Then we have great news for you!
Our colleagues are heading to Scandinavia next week with our company’s demo aircraft. And they are really looking forward to meet up with other flight enthusiasts. So if you’re interested, feel free to contact them at sponer@directfly.cz. And if that does not work out, you are always welcome at our home airport Brno-Medlánky.
