Articulation tests of standard and modified interphones conducted during flight at 5,000 and 35,000 feet, with appendices concerning: (1) interphone signal levels under various conditions; (2) temperatures encountered on high altitude missions; and (3) articulation in a B-26 bomber as a function of air speed. (OSRD, 1944; Publ. Bd., No. 5505.).

This paper aims to establish a thermal analysis model for stratospheric airships. Mixed convective heat transfer between envelope and air has been specially considered. Thermal analysis of HAB on the summer solstice was carried out in this paper, results show that forced convective heat transfer coefficient increases obviously as the air speed decreasing, which will enhance the heat transfer between envelope and atmospheric. The pressure difference decreases obviously as air speed increasing during the whole day. Therefore HAB(high altitude balloon) should increase the air speed to reduce the pressure difference, which will enhance the safety of HAB.

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A Note on the Time Required to make a Level Speed Measurement with a Turbine-Jet Aircraft

Journal of the Royal Aeronautical Society ◽

10.1017/s0368393100121686 ◽

1950 ◽

Vol 54 (478) ◽

pp. 651-655 ◽

Cited By ~ 1

Author(s):

K. J. Lush

Keyword(s):

High Altitude ◽

Sea Level ◽

Maximum Level ◽

Speed Measurement ◽

Wide Range ◽

Steady Level ◽

Air Speed ◽

Time Required ◽

Compressibility Effects

SummaryIt was desired to confirm quantitatively pilots’ impressions that on turbine-jet aircraft in the region of 40,000 ft. the level speed stabilised very slowly.The time required to make a conventional level speed measurement has been examined, for a representative turbine-jet aircraft, over a wide range of air speed and height. The results are compared with those for a typical piston-engined aircraft and their implications discussed.It is concluded that the time required to make a conventional level speed measurement increases rapidly with height, in the absence of compressibility effects on drag, and is about five times as great at 40,000 ft. as at sea level. It is inconveniently large at high altitude and level speed measurements there will require very long runs, unless it is arranged that each run is started at an air speed near the steady level speed.This increase will be present in most level speed tests, especially those in the region of the best speed for range. In maximum level speed measurements, however, compressibility effects may be present and the air speed may then be expected to settle down quickly.The need for long runs at high altitude is not peculiar to jet aircraft, but has come into prominence concurrently with them.

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Contrast of Filament Bright Rims

International Astronomical Union Colloquium ◽

10.1017/s0252921100025628 ◽

1994 ◽

Vol 144 ◽

pp. 365-367

Author(s):

E. V. Kononovich ◽

O. B. Smirnova ◽

P. Heinzel ◽

P. Kotrč

Keyword(s):

High Altitude ◽

Line Profile ◽

Line Center ◽

Magnetic Structures ◽

The Mean

AbstractThe Hα filtergrams obtained at Tjan-Shan High Altitude Observatory near Alma-Ata (Moscow University Station) were measured in order to specify the bright rims contrast at different points along the line profile (0.0; ± 0.25; ± 0.5; ± 0.75 and ± 1.0 Å). The mean contrast value in the line center is about 25 percent. The bright rims interpretation as the bases of magnetic structures supporting the filaments is suggested.

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Clean Electron Microscope Substrate Films Used for Micrometeorite Collection and Study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100061847 ◽

1967 ◽

Vol 25 ◽

pp. 366-367

Author(s):

D. M. Davies ◽

R. Kemner ◽

E. F. Fullam

Keyword(s):

Thin Film ◽

Electron Microscope ◽

High Altitude ◽

Amyl Acetate ◽

Temperature Variations ◽

Film Forming ◽

Film Specimen ◽

Particulate Contaminants

All serious electron microscopists at one time or another have been concerned with the cleanliness and freedom from artifacts of thin film specimen support substrates. This is particularly important where there are relatively few particles of a sample to be found for study, as in the case of micrometeorite collections. For the deposition of such celestial garbage through the use of balloons, rockets, and aircraft, the thin film substrates must have not only all the attributes necessary for use in the electron microscope, but also be able to withstand rather wide temperature variations at high altitude, vibration and shock inherent in the collection vehicle's operation and occasionally an unscheduled violent landing.Nitrocellulose has been selected as a film forming material that meets these requirements yet lends itself to a relatively simple clean-up procedure to remove particulate contaminants. A 1% nitrocellulose solution is prepared by dissolving “Parlodion” in redistilled amyl acetate from which all moisture has been removed.

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