Artem Kovalenko’s Post

The Robinson R-44 has been the best selling general aviation helicopter for many years. It's become so popular that it is ubiquitous even in Kamchatka. The experienced eye can easily recognize it even from afar thanks to it distinctive tall rotor mast. Why is it so tall? One of the reasons is the helicopter's size. To ensure safe clearance between the main rotor and the tail boom or ground obstacles in a smaller frame the mast was extended. But it's not the only reason. Frank Robinson designed its helicopters to be cheap, compact and simple. He opted for a two bladed rotor instead of a three bladed one to eliminate the need to fold it or take off for transport on a trailer. The compact design incorporates a teetering hinge mechanism in the main rotor. It's very cheap and simple and works like a seesaw, so when one blade rises, the other goes down. Because of this mechanism Robinson's rotor blades have a greater amplitude of vertical movement. To deal with it the manufacturer had to raise the main rotor up mounting it on the top of the tall rotor mast #aviation #helicopter #robinson #generalaviation #aerospaceengineering

We often state that airplane cabin air is fresh, but there's more to the story. While the air has a high recirculation rate and passes through HEPA filters, it's not quite the same as a refreshing sea breeze. The air taken from high altitudes is dry and contains ozone. In the 1960s and 70s, with an increase in flights at altitudes exceeding 27,000 feet, flight attendants began reporting rapid onset of fatigue. Studies revealed high cabin ozone concentration, significantly exceeding ground-level limits. To address this, new regulations were introduced to limit allowable ozone levels in the cabin. To achieve this, all aircraft flying above FL270 are equipped with ozone converters. Instead of filtering, these devices pass all cabin air through a catalyst grid that converts the highly reactive ozone (O3) into oxygen (O2). These converters also require periodic replacement #aviation #airplane #airport #dassault #falcon #businessjet #aerospaceengineering

While this Airbus A319 taxis for takeoff let's explore one of the systems that make our flights comfortable. Actually there is a special term in the aerospace industry for the aircraft interior temperature - 'The short-sleeve environment' meaning the interior where no extra clothing is needed . It's freezing cold at the altitude of a normal flight and without additional source of heating any possible insulation is useless. The pressurized part of the fuselage is always heated during flight. It's divided into several zones usually to adjust the temperature in each of them in the typical range within 18 to 30 degrees Celsius. The heat comes with the hot air through numerous vents and ducts. But contrary to the common misconception we need not to heat up the outside air to make it hot but actually to cool it down. The air for the cabin is taken from aircraft engines right after one of its compressor stages.The compressed air is very hot and needs to be cooled. To cool the hot air down we need to make it work to lose its energy - so on its way to the cabin it expands and rotates some turbines, mixes with other air and then reaches the comfortable temperature #aviation #airbus #commercialaviation #engineering #aerospaceengineering #airplane #aircraft

It seems like a new trend was set in the airliners fashion world. Both the Airbus A350 and Boeing 787 feature a distinctive nose shape. The smaller A220, SSJ and even newer designs adhere to this design principle. However this is not a stylistic choice. Everything in aerospace engineering is expensive and every step away from established reliable designs can be driven by potential benefits only. The Boeing 737 family inherited its nose shape from the 707 and 727 models. Boeing 777 retains the nose section of the Boeing 767. Similarly Airbus hasn't changed the nose shape of its widebody jets since the first A300. So what caused aircraft manufacturers to deviate from this tradition? The answer lies in advances in technologies and materials. Now engineers could use powerful new computational methods to create a nose shape that would reduce cockpit noise while improving the overall fuselage aerodynamics. The technology advancements made it possible to use large and curved glass panes for cockpit windshields.But just look at the nose shape of the early commercial jets like Comet and Caravelle to see that the history once again repeats #aviation #airplane #commercialaviation #aerospaceengineering #engineering #airbus #aircraft #aviationhistory

Flying over the sea on our way home. Everything in aviation is really expensive. A single main landing gear wheel may cost up to 6500 USD. One may think that if airlines operate big money daily it makes aviation a very profitable kind of business. Alas it's not true. Flying expensive things demands an impressive amount of money. Big revenues come along with big expenses. The typical airline profit margin is quite low. It has rarely exceeded 5% in modern commercial aviation history. The industrial forecast of net profit margin in 2024 is just 2,7%. This means for every 100$ of revenue an airline earns, they only keep 2,7$ as profit. For 2023 the corrected forecasted net profit margin was just 1,2%. There is a different way to look at profit, focusing on individual passengers. The average profit per passenger in 2023 was around 2,25$ per passenger. This means that every flight you took in 2023 bought airlines just a cup of coffee. Of course it's an average value. Profit vary depending on the routes, markets, business models and management efficiency #aviation #airplane #commercialaviation #airlines #aircraft #airlinebusiness

The Cessna 680 Sovereign is a great member of the successfully growing family of Cessna business jets. But how did it happen that Cessna, known for its general aviation workhorses, created the largest business jet fleet? The post World War II economic boom created the demand in faster transportation for executives and businessmen. The existing options were limited and airlines couldn't offer the needed flexibility in scheduling and access to smaller airports. Cessna and Beechcraft had already made their name in single piston props and even offered some twin engine options but the real fooray into the market was brought by the jet options. First business jets with a full single aisle cabin like Lockheed Jetstar, North American Sabreliner, Learjet 23 made it possible and proved that business jets can offer many opportunities. So while Beechcraft chose the way with turboprops and created its successful King Air family, Cessna decided to go jets and launched its long development of the Citation family which eventually became the world's largest family of business jets #aviation #businessjet #cessna #aviationhistory #airplane #aircraft #businessaviation

The Antonov An-12's instrument panel causes the same level of excitement and astonishment today as a modem glass cockpit would cause in the 50s. Of course this mind boggling amount of gauges would have been seen as a huge technological leap forward compared to the simpler cockpits of the 1920s. The technological development of aircraft led to increasing complexity of its systems. The complex systems needed humans attention to make sure that they function properly in flight thus making instrument panels in the cockpit more filled with instruments and indicators. The usual set of flight instruments needed to fly and navigate the aircraft got surrounded by numerous gauges for additional systems. The majority of this black panel is occupied with engine, landing gear, fire and navigation system instruments required constant crew monitoring. Modern glass cockpits have even more parameters to monitor but controlling them is largely automated. Instead of continuously monitoring system parameters the crew receives warnings only is something goes wrong or has a tendency to.This advancement was made possible by the development of the first color displays and microchips. #aviation #airplane #aircraft #cockpit #instrumentpanel #aviationhistory #technology #aerospacetechnology #flightsafety #engineering