Header1200x385

facebook_page_plugin
× Welcome to the CPL Aerodynamics question and answer forum. Please feel free to post your questions but more importantly also suggest answers for your forum colleagues. Bob himself or one of the other tutors will get to your question as soon as we can.

Angle of attack for Max endurance

  • Ryan1991
  • Topic Author

Ryan1991 created the topic: Angle of attack for Max endurance

Can some one please tell me what is the value of the angle of attack for Maximum endurance and angle of attack for Maximum range?
Thanks
#1

Please Log in or Create an account to join the conversation.

  • ZdrytchX

ZdrytchX replied the topic: Angle of attack for Max endurance

For small aircraft, maximum range AoA is the same as the for best climb AoA.

Maximum endurance is roughly halfway towards the critical angle of attack, but could vary with the aerofoil type greatly.

Just a reminder that endurance is to "reduce the sink rate" or to "stay in the air" the longest if you have fuel, while range is how far you can travel by gliding, or how fuel efficient you can travel distance wise. A powered aircraft usually has the best endurance in ground effect just over the lowest obstacle (because it requires the densest air) while best range is usually somewhere up high. But for an unpowered aircraft altitude provides the best endurance and glide range because you need altitude to sacrifice in the first place to get air time and range.

Best Endurance is usually portrayed as "most surplus power available" and for gliding, defining it gets a bit complicated (though in layman's terms you could say it provides the best lift to airspeed ratio) so generally they just teach students to glide at the best glide speed, which is also safer anyway because airspeed is critical for manoeuvring.

The angle of attacks aren't really defined in the manual of an aircraft as far as I can tell but for a cessna 172 it is around 8 degrees absolute angle of attack / 4 degrees angle of attack, and best endurance I believe is approximately an additional 4 degrees over that, though I have no evidence for that.

For now just accept that the angles of attack values vary from aircraft to aircraft and they generally the manuals only give you straight-line speeds that end up producing those angle of attacks, so in other words there is no definitive answer to your question
#2

Please Log in or Create an account to join the conversation.

Time to create page: 0.058 seconds