# [time-nuts] Need advice for multilateration setup

Bill Hawkins bill at iaxs.net
Sat Mar 28 22:34:51 EDT 2015

```An idea occurred (always a surprise):

The rocket's acceleration increases from 1 g as the mass of fuel is
ejected energetically, according to f=ma, with pretty constant force
from the motor. At some point, the fuel and oxidizer tanks are empty
(MECO), causing the acceleration to revert to 1 g or less, depending on
altitude. The change from max acceleration to free flight offers an
opportunity to calibrate the effect of max g on the oscillator. The
velocity is almost unchanged at that point, so the change in Doppler
shift comes only from the effect of acceleration on the oscillator. It
should be possible to use linear interpolation for the effect of
acceleration during powered flight, since f=ma is a first order
equation.

Bill Hawkins

-----Original Message-----
From: Bob Camp
Sent: Saturday, March 28, 2015 6:22 PM

The point being that, to even get acceleration into the picture, you
need have impossibly high accelerations .

At 10 G, your oscillator needs to be temperature  stable to < 0.01C to
even see the acceleration. If you are climbing 100K feet during the
acceleration phase the oscillator will see a *lot* more than that.

Bob

> On Mar 28, 2015, at 5:01 PM, Jim Lux <jimlux at earthlink.net> wrote:
>
> On 3/28/15 10:27 AM, Bob Camp wrote:
>> So If the rocket continuously accelerates  at 10,000 G's, you will
>> get a 20 ppm shift with typical sensitivity.  If you do this for very
long, you will also get into time dilation issues.
>> (you hit 0.1C in < 2 minutes).
>
> 10,000G is more like an artillery shell.
>
> A large amateur rocket might be more like 20-30G maximum.

```