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A new calculation of the opacity of high-temperature air (kT = 1 - 20 eV) is carried out. Line (bound-bound) transitions are included and LS term splitting of configurations is accounted for in the n = 2 and 3 levels. The primary purpose of the calculation is to remove the hydrogenic approximation to the dominant photoelectric and line transitions. In place of the hydrogenic approximation, Hartree-Fock-Slater matrix elements are used for the line transitions. For the photoelectric transitions, a combination of the Burgess-Seaton extension of the Coulomb approximation, and a high-energy acceleration-matrix-element Born approximation is employed. Comparisons are carried out with experiment and with previous calculations. A review and discussion is presented of the statistical mechanics of ionized gases, and some new results pertinent to the calculation of occupation numbers are presented.

An extensive tabulation of absorption coefficients of heated air was carried out with the aid of several large digital computer programs. These tables supersede the previous ones computed at Lockheed by Meyerott, Sokoloff, and Nicholls in 1959. Tables are presented for temperatures at every 1000 deg K between 1000 deg K and 24,000 deg K and for eight densities between ten times normal atmospheric to 0.000001 times normal. Absorption coefficients are individually listed for each of 14 contributing absorbers. The photon energy range is 0.6 -- 10.7 eV with a partition interval of 0.1 eV., Sponsored in part by DASA. See also Volume 1, AD0622797.

Contents: Theory of radiation in hot gases (elementary radiative transfer, theory of radiation, theory of molecular absorption); Spectral and mean absorption coefficients of heated air (historical review: research on hot gas absorption coefficients since 1900, general features of air absorption coefficients, molecular absorption coefficients, atomic absorption coefficients) ; Spectroscopic properties of six important band systems which contribute to the opacity of heated air., See also Volume 1, AD-654 054.

The report describes the results of flight trials, at night and in low visibility, with restricted peripheral vision. They were undertaken to discover whether lack of peripheral vision was a major cause of poor landing performance on conventional aircraft flight simulators. The results show that landing performance in flight is almost unaffected by loss of peripheral vision, even in poor visibility. (Author)

I.L.S. reflection interference should properly be considered as a feedback term in the study of control systems for automatic landing, but for convenience it has always been treated in a simpler open-loop fashion. The paper reports a qualitative study of the consequences of this simplification and finds them to be negligible both in control system analysis and in beam calibration procedures. (Author)

An extensive tabulation of absorption coefficients of heated air has been carried out with the aid of several large digital computer programs. These tables supersede the previous ones computed at Lockheed by Meyerott, Sokoloff, and Nicholls in 1959. Tables are presented for temperatures at every 1000 K between 1000 K and 24,000 K and for eight densities between ten times normal atmospheric to 0.000001 times normal. Absorption coefficients are individually listed for each of 14 contributing absorbers. The photon energy range is 0.6- 10.7 eV with a partition interval of 0.1 eV.

Calculations of the compositions of air, nitrogen, and oxygen were carried out to supplement the results given by F. R. Gilmore in RM-1543. Occupation numbers for atomic states in pure nitrogen and oxygen are given in 1,000K intervals for the temperature range from 10,000K to 24,000K. Species concentrations of air constituents are tabulated over this temperature range. Tables of occupation numbers for the atomic and molecular states of pure nitrogen and oxygen, computed by F. R. Gilmore but unpublished, which cover the range from 3,000K to 10,000K are also included. (Author), Rept. on Physics.

Analytic self-consistent field functions were determined for the 20 L-S coupled terms of the configurations 1s22s22pk3s, and for the 56 terms of the configurations 1s22s22pk3d where k = 0, 1, 2, 3. These functions were employed in the computation of oscillator strengths. Analytic self-consistent field wave functions are presented for ten terms in Be, B, C, F, and Ne. Radial equations for open-shell atoms in the unrestricted H-F approximation were derived in general form. A program was completed for the calculation of the continuum of the ground-state H-F operator in the application of the Goldstone many-body formalism to the calculation of correlation energies of finite atoms. An analysis of the Coulomb approximation (CA) of Bates and Damgaard is presented, by comparison of CA wave functions with H-F wave functions, and by a derivation of an approximate one-electron equation which indicates the choice of experimental energy parameter. A discussion of the normalization of CA wave functions is given along with a discussion of the relevance of effective range theory to the CA, and the calculation of some effective ranges in oxygen. Extended tables of CA radial dipole integrals are presented. (Author)