Aerospace industry technologies are always developing and every new aircraft seems to be revolutionary in some way. However, most of the attention and headlines seem to always go toward the big manufacturers, like Airbus and Boeing. What about the manufacturers of the smaller single-engine piston aircraft? What sort of progress are they making? Well, some recent developments, particularly in avionics, engines, and airworthiness standards, are paving the way for a bright future for general aviation.

Hawker and Cessna have both struggled recently, but Hawker has yet to recover like Cessna (Source: Cessna and Hawker Beechcraft annual reports)
As always, first some background of the business and general aviation market. In a nutshell, the segment has been fragile since the 2008 economic crisis, but has seen recent signs of recovery, albeit a slow one. Cessna and Hawker Beechcraft, two of the world’s largest general aviation manufacturers, have had to make large cutbacks in order to remain afloat. However, Hawker Beechcraft announced Chapter 11 bankruptcy protection in May and also recently announced that it would be selling most of its business to Chinese aerospace manufacturer Superior Aviation Beijing.
AVIONICS
One key technological development in general aviation has been in the field of cockpit avionics. Since around 2000, new production general aviation aircraft have had glass cockpit instruments installed as standard equipment. The new layout replaces the traditional round-dial, or analog, instruments and also consolidates the information that the pilot needs into two LCD screens.

The G1000 (top) with two LCD screens compared to the traditional scattered analog instruments (bottom)
Among other features, the glass cockpit also includes a moving map GPS and other optional features like NEXRAD weather information, Traffic Information Service (TIS, similar to the traffic avoidance system in airliners), and airport charts that you can pull up on the screens.
So what’s the big deal? They’re just some shiny new LCD screens, right? Well, to the non-pilot it may seem that way. To a pilot, it’s very valuable. What the glass cockpit does for us is increase our situational awareness, which is the perception of the environment around us at any given moment. With a moving map GPS, traffic information, weather information, and other features, the pilots have more information at their fingertips than ever before. With more information, pilots can make better decisions and avoid costly mistakes. Consider also the new Garmin Synthetic Vision Technology (below), which projects the terrain in front of the aircraft onto the left screen, called the Primary Flight Display. With this, flying at night and in poor weather becomes much safer since the pilot’s situational awareness is increased.

Synthetic Vision Technology enhances the pilot’s situation awareness by continuously projecting an image of the terrain around him
There are other advantages to glass cockpits besides increasing safety and situational awareness. The screens are modular and allow for quick and easy maintenance and replacement if necessary. Furthermore, a glass cockpit features more reliable and capable instruments. For example, in the old layout, a pilot would have to align the directional gyro, which indicates the aircraft’s heading, with the magnetic compass. In the G1000 layout, a pilot does not have to do that since the built-in magnetometer does that by itself. Also, the primary attitude indicator is no longer powered by a gyroscope, which can tumble if its limits are exceeded.
ENGINES
The other key technological development for general aviation aircraft is in propulsion. Traditionally, general aviation aircraft have been fueled with Avgas (aviation gasoline), also known as 100LL (low-lead). Avgas is essentially automobile gasoline with tetraethyl lead added, which boosts the octane rating and provides stable combustion at higher altitudes. It has been used in aircraft dating all the way back to World War II and it is widely available in countries with a large number of general aviation aircraft.
However, there is a problem with Avgas: it’s expensive. By now, we have all become accustomed to high gas prices, but you have not seen anything until you have filled up the tanks of a Cessna 172. Currently, the average price of Avgas in the U.S. is $6.26 per gallon (source: www.100ll.com), almost twice the average price of regular automobile gasoline. In a Cessna 172 that holds 56 gallons of fuel, that fill-up will set you back $350.56!

Jet-A and Avgas have followed the same price trends over the years, but Jet-A has always been cheaper (Source: U.S. Energy Information Administration)
So what is the alternative? Engine manufacturers have asked themselves that same question, and have since decided to develop diesel engines for general aviation aircraft that burn Jet-A fuel. Jet-A is the same fuel used by airliners and is basically pure kerosene. At the current average U.S. price of $5.41 per gallon, it’s also significantly cheaper and would mean filling up a Cessna 172 would cost $302.96, saving about $50. It’s still expensive, but it’s cheaper.
There are other advantages, too. Jet-A is more globally available than Avgas, opening up opportunities for new general aviation markets around the world. Also, Diesel engines have a comparatively low fuel burn, do not emit carbon monoxide, and are quieter since they do not operate at as high of a propeller speed. These are some of the advantages Cessna cited when announcing their new Jet-A powered version of the popular 182 model, dubbed the Turbo 182 NXT with a Safran engine. In addition, the plane will fly at 155 knots, cruise at altitudes up to 20,000ft, have a range of 1025 nautical miles, and will burn 11 gallons per hour. All of those parameters, especially the fuel burn, are unheard of for a turbopowered single-engine piston aircraft. It almost seems to good to be true to get all of those performance enhancements while paying less for the fuel.
AIRWORTHINESS STANDARDS
The last reason to believe in a bright future for general aviation is not a technological breakthrough, but rather a regulatory breakthrough. The developments that are taking place are in regards to Part 23 of the Federal Aviation Regulations, which outlines the airworthiness standards that all aircraft under a maximum gross weight of 12,500lb must meet in order to be certified. These regulations act alongside airworthiness standards for aircraft weighing greater than 12,500lb (Part 25) and rotorcraft (Parts 27 and 29).

The current spectrum of products weighing less than 12,500lb is significantly larger than it was 50 years ago (Source: Part 23 – Small Airplane Certification Process Study, FAA)
The problem is that when Part 23 was put into effect in 1965, the range of types of aircraft weighing under 12,500lb was fairly small. Now, you can find almost every type of aircraft in that category, from a two-seat single-engine piston to a small turbojet aircraft. Meanwhile, they are all bound by the same airworthiness standards under Part 23, which has become more expensive over the years to comply with due to the numerous rule additions and changes. In other words, the technology has far outpaced the regulations in place. Consequently, it has become more expensive to develop and certify a small simple piston aircraft since it must also meet the same standards as a small turbojet aircraft.
So what’s the solution? According to a 2009 FAA study on the matter, Part 23 rules should shift from being weight-based to being performance-based. The new three tier system would include low complexity and performance, medium complexity and performance, and high complexity and performance aircraft. Furthermore, it would apply to all aircraft weighing 19,000lb or less, an increase in scope from the previous 12,500lb limit.
When the rules do change, what would the impact be? I cannot imagine that the impact would be anything but good. As a result of a tiered certification process, manufacturing and certification costs can be cut, which would further result in a lower final price for the consumer.
CONCLUSION
Developments in avionics, engines, and certification standards are reasons to believe that the general aviation sector is still alive, despite the slow economy and recoveries of the major manufacturers. Of course, these challenges will not be accomplished overnight, but significant progress should be made in the long term, let’s say the next 10 years.