27-03-2007, 15:40
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חבר מתאריך: 28.09.04
הודעות: 5,686
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אם זכרוני אינו מטעה אותי, מדובר בסביבות 20G בנטישה
אך פרק הזמן קצר ביותר וכמעט לא מספיק להשפיע בכיוונים של "שחור בעיניים" או איבוד הכרה, כפי שיכול להגרם מג'י הרבה יותר נמוך אך לאורך זמן ממושך יותר.
מצד שני, אם הידיים לא הוחזקו כראוי, יכולה להיגרם פריקה (מפרק הכתף יוצא ממקומו כלפי מטה).
עריכה: מצאתי את המידע הבא באתר:http://www.ejectionsite.com/
The maximum G-force that is experienced depends on several factors of the propulsion system in the seat, and in the mass of the seat/man combination. As there are many different designs of seats and propulsion systems, it is hard to generalize this. The older purely ballistic seats tended to be higher ranges, from 17-22Gz not being unusual. Later designs lowered the maximum G force as the addition of rocket propulsion allowed for seats to clear the aircraft with less initial force. The newer seats are often in the range of 12-14 Gz. This varies by temperature as well, with the hotter cockpit temperature allowing for a higher impulse from the cartridges.
The other major factor is the mass of the seat/man package. Often referred to as the total ejected mass, this is a measurement of the mass of the seat, the survival equipment, and the crewman and his/her total body mass along with the mass of the gear he/she is wearing. In current issue seats, the amount of force from the catapult and rocket is not variable so the lighter the crewman the higher the amount of force. The reverse holds true for the heavier crewman up to a point, where the total mass of the seat/man begins to cause excessive inertia to build up on the catapult. This would allow gas pressure to build higher and thus provide a higher force when the inertia is finally overcome.
Another force that is often involved in this calculation is the amount of G force the aircraft, and its occupant are experiencing when the seat fires. This has an additive effect similar to that of the higher weight occupant. Since all these forces vary from one ejection to another, a range of force is often specified for a particular seat based on the average crewman on the average day.
נערך לאחרונה ע"י yaari בתאריך 27-03-2007 בשעה 15:52.
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