Tests of a 1/7-Scale Semispan Model of the XB-35 Airplane in the Langley 19-Foot Pressure Tunnel

Description:

A 1/7 scale semispan model of the XB-35 airplane was tested in the Langley 10 foot pressure tunnel, primarily for the purpose of investigating the effectiveness of a leading-edge slot for alleviation of stick-fixed longitudinal instability at high angles of attack caused by early tip stalling and a device for relief of stick-free instability caused by elevon up-floating tendencies at high angles of attack. Results indicated that the slot was not adequate to provide the desired improvement in stick-fixed stability. The tab-flipper device provided improvement in stick-free stability abd two of the linkage combinations tested gave satisfactory variations of control force with airspeed for all conditions except that in which the wing-tip "pitch-control" flap was fully deflected. However, the improvement in control force characteristics was accompanied by a detrimental effect on stick-fixed stability because of the pitching moments produced by the elevon tab deflection.

Creator(s):
Creation Date: January 16, 1946
Partner(s):
UNT Libraries Government Documents Department
Collection(s):
National Advisory Committee for Aeronautics Collection
Technical Report Archive and Image Library
Usage:
Total Uses: 39
Past 30 days: 9
Yesterday: 4
Creator (Author):
Creator (Author):
Creator (Author):
Date(s):
  • Creation: January 16, 1946
Description:

A 1/7 scale semispan model of the XB-35 airplane was tested in the Langley 10 foot pressure tunnel, primarily for the purpose of investigating the effectiveness of a leading-edge slot for alleviation of stick-fixed longitudinal instability at high angles of attack caused by early tip stalling and a device for relief of stick-free instability caused by elevon up-floating tendencies at high angles of attack. Results indicated that the slot was not adequate to provide the desired improvement in stick-fixed stability. The tab-flipper device provided improvement in stick-free stability abd two of the linkage combinations tested gave satisfactory variations of control force with airspeed for all conditions except that in which the wing-tip "pitch-control" flap was fully deflected. However, the improvement in control force characteristics was accompanied by a detrimental effect on stick-fixed stability because of the pitching moments produced by the elevon tab deflection.

Language(s):
Subject(s):
Keyword(s): aircraft stability and control
Contributor(s):
Serial Title: NACA Memorandum Report
Partner:
UNT Libraries Government Documents Department
Collection:
National Advisory Committee for Aeronautics Collection
Collection:
Technical Report Archive and Image Library
Identifier:
Resource Type: Report
Format: Text
Rights:
Access: Public
Statement: No Copyright, Unclassified, Unlimited, Publicly available