TECHNOLOGY: FRIEND
OR FOE?
By Rich Hanson, AMA President | richh@modelaircraft.org
SINCE ITS INCEPTION, AMA has served to foster and promote scientific development and technological advancements in model aeronautics and its contribution to the greater aeronautical and aerospace community. As stated in the AMA Bylaws, the primary objective of AMA is to “promote and foster educational and scientific advancement in model aeronautics” and “encourage the study and discussion of scientific problems and to disseminate scientific news and views.”
Model aviation has realized scientific achievements and extensive technological advancements in nearly every aspect of the hobby. It has also experienced significant advancements in aeronautical design and control functions; building materials; finishing features and techniques; assembly adhesives; powerplants, battery supply, and propulsion systems; radio control spectrum and frequency applications; and the introduction of numerous microelectronic flight augmentation components.
With each advancement, AMA and the aeromodeling community have adapted to the modern technology and safely assimilated it into the hobby. That stated, not all new ideas were successful, and not all concepts were fully embraced, often having the effect of spinning off new disciplines within the hobby. Still others were short-lived, ultimately becoming antiquated and replaced by newer ideas and concepts.
One of the more recent technologies introduced is the Sensor Assisted Flight Envelope (SAFE) technology. This technology is a flight stabilization system developed by Spektrum RC (Horizon Hobby) and designed primarily for beginner and trainer RC airplanes. It’s designed to make learning to fly easier and less prone to crashes by providing various levels of assistance.
SAFE technology’s core principle employs a combination of multi-axis sensors (gyroscopes and accelerometers) and intelligent flight control software within the receiver to constantly monitor the aircraft’s attitude (its orientation relative to the horizon). This “attitude awareness” is what allows SAFE to provide its protective and assistive features.
Key Features of SAFE Technology
- Flight Envelope Protection: This is the most significant benefit. SAFE establishes an “electronic flight envelope” that prevents the model from entering extreme or unusual attitudes (e.g., steep dives or excessive bank angles).
- Pitch and Roll Angle Limits: In Beginner mode, SAFE will limit how far the aircraft can pitch up and down or roll left and right. This helps prevent overcontrolling and keeps the airplane in a stable, controllable attitude.
- Self-Leveling: When the pilot releases the control sticks to neutral, SAFE automatically returns the aircraft to a level flight attitude. This is incredibly helpful for beginners who might struggle with maintaining orientation.
- Multiple Flight Modes: SAFE typically offers progressive flight modes that allow pilots to gradually increase their skill level.
- Beginner Mode: Provides the most assistance, with tight pitch and roll limits and strong self-leveling. It often assists with takeoffs and landings.
- Intermediate Mode: Offers more freedom than Beginner mode, with larger flight-envelope limits but still provides some self-leveling and envelope protection.
- Experienced (or Advanced) Mode: In this mode, SAFE generally offers little to no flight envelope protection; however, the underlying Artificial Stabilization 3-Axis System (AS3X) technology might still be active to smooth turbulence.
- Panic Recovery Mode: This is a “get out of jail free” card. At the flip of a switch, Panic Recovery mode instantly returns the aircraft to level flight from nearly any orientation. This gives pilots confidence to try new maneuvers, knowing that they have a safety net if they get into trouble.
- AS3X Technology: AS3X is often integrated with SAFE technology. While SAFE focuses on limiting the flight envelope and providing self-leveling, AS3X works behind the scenes to actively counter external forces, such as wind, turbulence, and torque. It makes the aircraft fly smoother and feel locked in, giving the pilot a more precise and natural control feel, even in challenging conditions. AS3X operates even in the more advanced flight modes where envelope protection might be off.
- Progression: The multiple flight modes allow pilots to gradually transition from highly assisted flight to full manual control as their skills improve.
Benefits
- Easier Learning Curve: SAFE significantly reduces the difficulty and frustration of learning to fly RC models.
- Reduced Crashes: By preventing extreme maneuvers and offering self-correction, SAFE helps minimize costly and discouraging crashes.
- Increased Confidence: Pilots can experiment and push their skills, knowing they have the safety nets of flight envelope protection and panic recovery.
Although SAFE technology is a fantastic tool for beginners by providing flight control assistance and reducing the risk of crashing, it’s important to remember that it’s an assistive system. Pilots still need to learn fundamental flying skills and eventually learn to fly without reliance on SAFE to truly master the hobby.
AMA Introductory Pilots are split on whether the use of SAFE technology is appropriate for use in training new RC pilots. Although there is no doubt that this technology is beneficial for those who choose to train themselves by trial and error, some introductory pilots profess that the system instills improper control techniques that lead to subsequent crashes from overcontrolling the aircraft when flying without SAFE technology assistance. Others believe that the penchant to overcontrol that is attained in SAFE mode can be effectively corrected by proper methods of instruction and progressive convergence from beginner to advanced flight modes.
I believe that SAFE technology is a highly effective tool for beginners who are attempting to fly on their own or for individuals who are learning to fly in a club environment. This assistive feature lowers the risk of crashes, lowers loss anxiety, boosts the confidence and enjoyment of newcomers to the RC world, and shortens the time needed to become an accomplished and proficient RC pilot.
Keep ’em safe, keep ’em flying, and continue to enjoy this great hobby!
