Re: Flying High ?

Date:         03 Mar 98 03:12:52 
From:         Stuart Bruff <stuart.bruff@gecm.com>
Organization: GEC-Marconi
References:   1 2
Followups:    1
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Chris Pitzel wrote:
> The earth's gravitational attraction decreases
> For example, I weigh roughly 130 pounds at sea level, yet I
> would only weigh perhaps 110 pounds at 40k feet.

I think that may be a little optimistic

G	6.6700E-11		g0		wt
Re	6.3780E+06 m		9.8052 ms-2	130.0000 lbs
Me	5.9800E+24 kg

Alt(m)	Reff (m)		galt	galt/g0	wt at alt	Alt (ft)
0	6.3780E+06		9.8052	1.0000	130.0000	0
1000	6.3790E+06		9.8022	0.9997	129.9592	3281
2000	6.3800E+06		9.7991	0.9994	129.9185	6562
3000	6.3810E+06		9.7960	0.9991	129.8778	9843
4000	6.3820E+06		9.7929	0.9987	129.8371	13123
5000	6.3830E+06		9.7899	0.9984	129.7964	16404
6000	6.3840E+06		9.7868	0.9981	129.7558	19685
7000	6.3850E+06		9.7837	0.9978	129.7151	22966
8000	6.3860E+06		9.7807	0.9975	129.6745	26247
9000	6.3870E+06		9.7776	0.9972	129.6339	29528
10000	6.3880E+06		9.7746	0.9969	129.5933	32808
11000	6.3890E+06		9.7715	0.9966	129.5527	36089
12000	6.3900E+06		9.7684	0.9962	129.5122	39370
13000	6.3910E+06		9.7654	0.9959	129.4717	42651
14000	6.3920E+06		9.7623	0.9956	129.4312	45932
15000	6.3930E+06		9.7593	0.9953	129.3907	49213
16000	6.3940E+06		9.7562	0.9950	129.3502	52493
17000	6.3950E+06		9.7532	0.9947	129.3098	55774
18000	6.3960E+06		9.7501	0.9944	129.2693	59055
19000	6.3970E+06		9.7471	0.9941	129.2289	62336
20000	6.3980E+06		9.7440	0.9938	129.1885	65617

110.0 lbs = 0.8462g = 8.2967 ms-2 : at alt = 555617 m = 1822890 ft = 345
miles

Of course, I've probably got my sums wrong ...

Stuart Bruff