FP-C® Review: Aircraft Fundamentals, Safety, and Survival - Part 2: Aircraft Fundamentals So How Does An Aircraft Fly? It’s PFM!
Note: All Aircraft Performance Data is Based on Standard Atmospheric Pressure of 29.92 and Temp of 15C
all aircraft fly by overcoming the forces of nature drag and gravity So how does an aircraft overcome DRAG and GRAVITY? lift overcomes gravity thrust overcomes drag Lift > Gravity = Climb Lift = Gravity = Level Flight
2014 FAA Safety Updates - http://www.faa.gov/news/fact_sheets/news_story.cfm?newsId=15794 Tell me about aircraft controls. Rotor Wing Cyclic pitch roll Foot Pedals Yaw Collective climb decent acceleration Horizontal Stabilizer Resists roll and pitch Vertical Stabilizer (tail) Resists yaw
Fixed Wing Cyclic or Yoke Pitch roll Foot Pedals Yaw Throttle power for acceleration Ailerons Mounted on main wing, controls roll Elevators Mounted on horizontal stabilizer, controls pitch Rudder Mounted on vertical stabilizer, controls yaw Flaps Mounted on main wing, controls drag and lift
What affects aircraft performance? many factors Type and numbers engines Aircraft design Weight (Max Gross Weight) Each aircraft is slightly different Affects the structural integrity of air frame. Temperature Hotter air produces less performance Humidity Water vapor is less dense than dry air Also has negative effect engines due to less o2 available for combustion Altitude Air is less dense Wind Direction and Speed Always try to take off into wind. Ground Effect Generally when an aircraft is within it’s wing length from the ground. Air flowing over wing compresses between wing and ground improving aircraft performance.
Density Altitude: Combination of true altitude MSL, Atmospheric Pressure, Temperature, and Humidity.
So how does weather affect an aircraft’s ability to fly? Wind Generally doesn’t affect an aircraft's ability to fly could delay a flight due to crews inability to properly care for patient. Rain Also doesn’t generally affect an aircraft's ability to fly unless it affects visibility Thunderstorms Avoid Lightning Microbursts Strong sudden down drafts that can cause a sudden loss of altitude
Snow Generally doesn’t affect ability to fly unless visibility is affected below minimums Ice Unless equipped with deicing equipment, aircraft's are unable to fly in icing conditions changes the shape wing causing a decrease in lift adds weight to aircraft Reduced visibility Any condition that reduces visibility below determined minimum for an VFR program is grounds for declining a flight Temperature Most aircraft are not limited by temperatures, however there are exceptions Temperature alone generally doesn’t prevent an aircraft from flying come aircraft to have high temp limitations High temps can affect an aircraft's performance (Density Altitude) Crews ability to care for patients can be effected if temperatures are extreme, and may be ground for declining flight
What is VFR vs. IFR VFR Visual Flight Rules Rules that most helicopter services fly by In short, it means you must be able to see the ground, and be able to fly visually. Weather Minimums for VFR vary by area but are generally roughly 1000-1500 ft ceiling and 3-5 miles visibility IFR Instrument Flight Rules Weather Conditions that require the use of instruments to navigate due to a loss of visual cues. Few helicopter services have ability to fly fir most fixed wing services can fly IFR. Still require minimum visibility of runway in order to land IIMC (Double I MC) Inadvertent Instrument Meterological Conditions An emergency situation where an aircraft, operating under Visual Flight rule, inadvertently finds themselves in low, or zero, visibility conditions. The only safe solution is to CLIMB!!!
The SAD Outcome of an IIMC situation!