[VSKYLABS Newsletter] issued 11 Jul 2024
Hello VSKYLABS Test-Pilots!
A new helicopter will soon join the VSKYLABS Helicopters fleet!
It is the VSKYLABS 'Test-Pilot': 902X-NTR! (X-Plane 12)
Why developing a VSKYLABS No-Tail-Rotor Heli in X-Plane 12???
The 'short' answer is: Because it is a HUGE challenge, and because X-Plane 12 is the PERFECT scientifically-based test-bed flight simulation environment which can cover *ALL* aspects in a no-tail-rotor simulation!
In this newsletter, in the light of the upcoming VSKYLABS ‘Test-Pilot’: 902X-NTR Project, we will dive deep into better understanding of NOTAR (No TAil Rotor) technology.
*Development notice: The VSKYLABS 'Test-Pilot': 902X-NTR Project is an independent VSKYLABS development effort focused on engineering and simulating a highly defined, twin-turbine NOTAR helicopter propulsion system. The development effort, and the resulting project are VSKYLABS-independent and not affiliated with, or related to 'MD Helicopters' or any other company/entity.
The (real-world) MD 902 Explorer stands out in its class for its advanced technology, operational versatility, and safety features, making it a preferred choice for many critical applications.
Let’s dive into some of the core elements in the design of the real-world MD 902 Explorer, which serves as the engineering 'case study' for the development of the VSKYLABS 902X-NTR Project for X-Plane 12:
The MD 902 Explorer is a light twin-engine helicopter developed by McDonnell Douglas Helicopter Systems, now part of MD Helicopters. Known for its innovative design, the MD 902 features the NOTAR (NO TAil Rotor) anti-torque system, which enhances safety, reduces noise, and improves performance. First flown in December 1992 and entering service in the mid-1990s, the MD 902 Explorer is popular for a variety of applications, including emergency medical services, law enforcement, executive transport, and search and rescue operations. Its advanced avionics, spacious cabin, and exceptional maneuverability make it a versatile and reliable choice for operators worldwide.
Key features in the MD 902 Explorer NOTAR engineering:
NOTAR (No Tail Rotor) System: Instead of a traditional tail rotor, the MD 902 uses the innovative NOTAR system for anti-torque control. This system directs fan exhaust through the tail boom, reducing noise, minimizing pilot workload, and enhancing safety, particularly in confined areas and offshore platforms
Engines: The MD 902 is powered by two Pratt & Whitney Canada PW206E or PW207E turboshaft engines, delivering robust performance and reliability. These engines provide a maximum cruise speed of approximately 131 knots and a range of 328 nautical miles.
Rotor System: The five-blade main rotor system is fully articulated and features bearingless composite flexbeams. These components contribute to smooth flight characteristics and low maintenance requirements.
Construction and Safety: The airframe is constructed from composite materials, providing corrosion resistance and integrated lightning protection. The helicopter is designed with high crashworthiness, capable of withstanding impacts of up to 30 Gs at 30 feet per second.
Versatility: The MD 902 Explorer is used in various roles, including air medical services, law enforcement, search and rescue, VIP transport, and offshore operations. It is valued for its spacious cabin, which can be configured to meet different mission requirements.
Operators: This helicopter is used by various organizations worldwide, including air ambulance services, law enforcement agencies, and more.
Key features in the upcoming VSKYLABS 902X-NTR engineering in X-Plane 12:
The VSKYLABS 902X-NTR is being developed as a true No-Tail-Rotor helicopter simulation using X-Plane 12's cutting-edge physics and flight dynamics innovations. This means true physics and aerodynamics—no tricks, no hidden tail rotors, or other disguises.
The VSKYLABS 902X-NTR propulsion system simulation covers the key elements of the no-tail-rotor propulsion system:
(Simulated) Turboshaft Propulsion: Highly defined simulation of twin PW207E turboshaft engines in X-Plane 12.
(Simulated) Fan System: A core component of the No-Tail-Rotor propulsion system, located within the helicopter's extended engine/tailboom compartment, which pushes ambient air into the tailboom.
(Simulated) Coanda Effect Forces on the Tailboom: Pressurized air is expelled through two slots running along the tailboom, creating a boundary layer that adheres to the surface. This effect generates lift on the tailboom, counteracting the main rotor’s torque.
*The Coanda Effect Forces are not being directly simulated in X-Plane and in the model. However, the calculated/estimated additive forces are being added to the overall anti-torque real-time simulation.
(Simulated) Direct Jet Thruster: Located at the end of the tailboom, this thruster provides additional control by adjusting the direction and amount of expelled air. It aids in maintaining directional stability and control during hover and forward flight.
(Simulated) The Unique Vertical Stabilizers System: The twin vertical stabilizers can move to provide additional yaw control and stability. This is important for the following reasons:
- Enhanced Yaw Control: Movable vertical stabilizers assist in fine-tuning yaw control, which is crucial for hovering and low-speed maneuvers. This helps compensate for varying wind conditions and directional changes.
- Improved Stability: During forward flight, movable vertical stabilizers contribute to maintaining directional stability and balance, which are vital for smooth and controlled flight.
The VSKYLABS 'Test-Pilot': 902X-NTR Project is currently one of the leading development efforts at VSKYLABS and is already in advanced stages. The release is expected soon, so stay tuned!
Here's a short video showing some of the 'behind the scenes Bloopers' during the early development, setup and engineering of the complex NTR simulation:
Fly safe!
VSKYLABS