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where: $\gamma$ is the density of the atmospheric medium, $r_a$ the particle radius for 1.5 $\mu$ m. The velocity of laminar noiseless motion is shown below
For this situation Re must be $\leq 10$ (since the radius of the particles, their velocity for $\gamma = 1.29 \, \text{kg.m}^{-3}$ must be inter-related by the conditions $r_a
Particle Radius
1.5 $\mu$ m
0.05mm
Velocity(metres per.second).
280[1]
3
2340[2]
Notes: [1] Up to an altitude of 3Km
[2] At an altitude of 15Km, where the density of the atmosphere has decreased.
11. It is therefore noted that, at 15Km altitude, the aerosol cloud can move at up to about seven times the speed of sound. Hence, this correlates with reports of fast-moving UAPs, much faster than aircraft. An aqueous aerosol moves at high velocity and evaporates quickly. Hence, life time can be short. A long-lived aerosol cloud forming a UAP can only consist of solid dust particles of very small size.
12. The energy of the EM field in the cloud and the aerodynamic (i.e. atmospheric) drag force are proportional to the cloud volume. Therefore the velocity and path taken should not depend on cloud dimensions. For example, if a charged aerosol cloud has moved distance L (e.g. 40km) with a velocity v (e.g. 30ms⁻¹) a volume density can be calculated (in this case $4 \times 10^3 \, \text{m}^3$ ).
13. Lights For a high field potential (e.g. $>10^5 \, \text{V.m}^{-1}$ ) an electrodeless corona discharge should occur in the zones of maximum E field intensity; giving rise to light emission from the aerosol cloud. If the field intensity varies throughout the aerosol, localised luminous zones can occur - due to alternate regions of maxima and minima. Hence, it is postulated that ‘navigation lights’ are reported. In the E₁₁ mode, for example two ‘lights’ or a luminous strip can be formed. If the number of discharge zones increases, the number of ‘lights’ will increase which will be equally distributed around the cloud as luminous zones or ‘portholes’.
14. Colours It is suggested that different colours might be produced by the presence of particles in the discharge zones.
15. Electrical Attraction If the discharge connects with some conducting object (Earth’s surface or aircraft), the ‘beam’ causes the aerosol cloud to re-orientate and even move along with a moving object such as an aircraft.
16. It is postulated that when ‘searchlight beams’ are reported from UAPs that most of the energy is concentrated in a discharge cone and can cause damage by the high voltage but very small intensity current. This can lead to involuntary closure of electronic and electrical circuits (switches) and have adverse health effects on humans (see Working Paper No. 25). On the ground the discharge can leave marks, bend grass etc.
19-3
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