Fuel-Optimal Retrothrusted Soft Landing Through an Atmosphere,

Abstract

A simple analysis of the problem of achieving a soft landing for airdrop by fitting the payload with retrorockets, and a direct iterative numerical procedure for determining the switch-on point for minimal fuel consumption, in terms of either time or altitude. Through appropriate reversals of sign, the formulas may also be used for ascent trajectories of full-thrust, vertically boosted rockets where the assumption of a constant gravity field is acceptable. Since the unretrothrusted portion of the descent is identical with free fall, the dynamical equations are integrable in closed forms. For a constant atmosphere, closed form analytic solution is also obtained for the retrothrusted descent. For an exponentially varying atmosphere, however, one cannot escape a numerical integration of the dynamical equations. (Author)

Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1970
Accession Number
AD0718405

Entities

People

  • M. L. Juncosa

Organizations

  • RAND Corporation

Tags

Communities of Interest

  • Weapons Technologies

DTIC Thesaurus Topics

  • Altitude
  • Ascent Trajectories
  • Atmospheres
  • Equations
  • Fuel Consumption
  • Landing
  • Numerical Integration
  • Soft Landings
  • Trajectories

Readers

  • Aerial Delivery - Logistics and Supply Chain Management.
  • Calculus or Mathematical Analysis
  • Control Systems Engineering.