Author: B. M. CrenshawPublisher:
ISBN:
Category :
Languages : en
Pages : 346
Book Description
Aircraft Landing Gear Dynamic Loads from Operation on Clay and Sandy Soil
Author: B. M. CrenshawAircraft Landing Gear Dynamic Loads Induced by Soil Landing Fields. Volume I. Prediction Model and Wheel Loads
Author: B. M. CrenshawPublisher:
ISBN:
Category :
Languages : en
Pages : 189
Book Description
A mathematical model to predict sinkage and the resulting loads for aircraft wheels operating on bare soil surfaces is presented together with experimental results for a 29 x 11-10 8PR Type III tire. Four primary factors which determine soil rutting and drag consist of the tire spring rate, the soil load deflection relation, a drag inertia force, and a lift inertia force. Soil load deflections are based on the mobility number concept. Empirical constants were used to compute the inertia forces. Comparisons of predicted and measured rut depths and drag loads are made for a clay soil with CBR(California Bearing Ratio) ranging from 1.5 to 2.3 and speeds from 0 to 90 knots for tire inflation pressures of 30, 45, and 70 psi. Similar comparisons are made for sand having a surface strength of CBR 1.5. The experimental program included 173 tests with a single wheel and 39 tests with two wheels in tandem on buckshot clay and 24 single wheel tests on sand.
Aircraft Landing Gear Dynamic Loads Induced by Soil Landing Fields. Volume II. Soil Tests and Soil Response Studies
Author: W. B. TruesdalePublisher:
ISBN:
Category : Runways (Aeronautics)
Languages : en
Pages : 165
Book Description
This report contains the results of the construction and maintenance of the buckshot clay test bed used for tandem and single wheel high speed landing gear tests conducted at the NASA Langley Landing Loads Track. The test bed was constructed to a CBR strength of 2.7, moisture content of 32.5 percent, dry density of 86.0 pcf, degree of saturation of 91.7 percent, and airfield penetration resistance of 1.7 to 1.8. Analysis of dynamic soil behavior indicated that wave propagation velocities in the soil and soil inertia effects become significant at forward velocities greater than 60 knots. Strain-rate effects are significant at all velocities for buckshot clay and cause 50 to 60 percent increases of shear strength at a forward velocity of 50 knots. Strain-rate effects on sand are insignificant except when pore pressures are developed. The wheel will 'outrun' the bow wave or shear wave propagating ahead of the wheel at forward velocities greater than the 150 to 250 knot range.
NASA Technical Note
Author: Laboratory Shear Strength of Soil
Author: Raymond Nen YongPublisher: ASTM International
ISBN: 9780803107892
Category : Science
Languages : en
Pages : 736
Book Description
Laboratory Shear Strength of Soil
Author: Ramond Nen YongPublisher: ASTM International
ISBN:
Category : Shear strength of soils
Languages : en
Pages : 721
Book Description
Report No. FHWA-RD.
Author: United States. Federal Highway Administration. Offices of Research and DevelopmentPublisher:
ISBN:
Category :
Languages : en
Pages : 766
Book Description
Aircraft Tire Behavior During High-speed Operations in Soil
Author: Trafford J. W. LelandPublisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 68
Book Description
Technical Abstract Bulletin
Author: Soil Mechanics for Off-road Vehicle Engineering
Author: Leslie L. KarafiathPublisher:
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 526
Book Description