ESDU 80020
Average downwash at the tailplane at low angles of attack and subsonic speeds.
Abstract:
ESDU 80020 contains a simple method for estimating the average downwash angle at the tailplane for subsonic speeds and low angles of attack where the lift, pitching moment and downwash characteristics are linear, i.e. where the flow is wholly attached. The method, which is semiempirical, is a first order one allowing for the major effects of wing planform, body, wingbody interference and tailplane height. Moderate amounts of wing twist are acceptable in the method. The method applies only to wingbodytail combinations although some assessment of the effect of rearfuselage mounted nacelles is given. A computer program of the method is provided as ESDUpac A8020. ESDU 97021 provides a method for estimating the effect of flap deployment on the average downwash angle at the tailplane low speeds.Indexed under:
Details:
Data Item ESDU 80020  

Format: 

Status: 

Previous Releases:  
ISBN: 

The Data Item document you have requested is available only to subscribers or purchasers.
 Subscribers login here.
 If you are not an ESDU subscriber you can
 find out how to subscribe, or
 purchase this Data Item from the IHS Standards Store.
This Data Item is complemented by the following software:
Name  Details  

ESDUpac A8020 
This program is only available to subscribers. 
The graphs listed below are available only to subscribers.
 Subscribers login here.
 If you are not an ESDU subscriber find out how to subscribe.
This Data Item contains 26 interactive graph(s) as listed below.
Graph  Title 

Figure 1a  Downwash parameter at an infinite distance downstream. λ = 0 
Figure 1b  Downwash parameter at an infinite distance downstream. λ = 0.25 
Figure 1c  Downwash parameter at an infinite distance downstream. λ = 0.5 
Figure 1d  Downwash parameter at an infinite distance downstream. λ = 1.0 
Figure 2  Downwash parameter for elliptical loading 
Figure 3  Correction to downwash parameter 
Figure 4a  Factor for average downwash across tailplane: A tan Λ_{1/2} = 0. λ = 0 
Figure 4b  Factor for average downwash across tailplane: A tan Λ_{1/2} = 0. λ = 0.25 
Figure 4c  Factor for average downwash across tailplane: A tan Λ_{1/2} = 0. λ = 0.5 
Figure 4d  Factor for average downwash across tailplane: A tan Λ_{1/2} = 0. λ = 1.0 
Figure 5a  Factor for average downwash across tailplane: A tan Λ_{1/2} = 2. λ = 0 
Figure 5b  Factor for average downwash across tailplane: A tan Λ_{1/2} = 2. λ = 0.25 
Figure 5c  Factor for average downwash across tailplane: A tan Λ_{1/2} = 2. λ = 0.5 
Figure 5d  Factor for average downwash across tailplane: A tan Λ_{1/2} = 2. λ = 1.0 
Figure 6a  Factor for average downwash across tailplane: A tan Λ_{1/2} = 4. λ = 0 
Figure 6b  Factor for average downwash across tailplane: A tan Λ_{1/2} = 4. λ = 0.25 
Figure 6c  Factor for average downwash across tailplane: A tan Λ_{1/2} = 4. λ = 0.5 
Figure 6d  Factor for average downwash across tailplane: A tan Λ_{1/2} = 4. λ = 1.0 
Figure 7a  Factor for average downwash across tailplane: A tan Λ_{1/2} = 6. λ = 0 
Figure 7b  Factor for average downwash across tailplane: A tan Λ_{1/2} = 6. λ = 0.25 
Figure 7c  Factor for average downwash across tailplane: A tan Λ_{1/2} = 6. λ = 0.5 
Figure 7d  Factor for average downwash across tailplane: A tan Λ_{1/2} = 6. λ = 1.0 
Figure 8  Effect of body 
Figure 9  Effect on tailplane height 
Figure 10  Downwash at zero lift 
Figure 11  Mach number effect 
Explore ESDU
ESDU Series:
 Aerodynamics
 Aircraft Noise
 Composites
 Dynamics
 Fatigue  Endurance Data
 Fatigue  Fracture Mechanics
 Fluid Mechanics, Internal Flow
 Fluid Mechanics, Internal Flow (Aerospace)
 Heat Transfer
 Mechanisms
 Performance
 Physical Data, Chemical Engineering
 Stress and Strength
 Structures
 Transonic Aerodynamics
 Tribology
 Vibration and Acoustic Fatigue
 Wind Engineering
ESDU Packages:
See this document in context
ESDU Series
Copyright © 2020 IHS Markit. All Rights Reserved