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CX2SA > SATDIG 10.08.09 04:41l 1126 Lines 39581 Bytes #999 (0) @ WW
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Today's Topics:
1. New Cubesat - the Ultimate Fox Hunt (Bob Bruninga )
2. FT-736r com port settings. (Norman W Osborne)
3. Re: New Cubesat - the Ultimate Fox Hunt (Joe)
4. Re: FT-736r com port settings. (Greg D.)
5. WD9EWK from DM54/DM55 - report (Patrick STODDARD (WD9EWK/VA7EWK))
6. keps (Nigel Gunn G8IFF/W8IFF)
7. Re: New Cubesat - the Ultimate Fox Hunt (G0MRF@xxx.xxxx
8. Re: New Cubesat - the Ultimate Fox Hunt (Joe)
9. Re: New Cubesat - the Ultimate Fox Hunt (Jim Jerzycke)
10. Re: New Cubesat - the Ultimate Fox Hunt (Pete Rowe)
11. Re: New Cubesat - the Ultimate Fox Hunt (Lee McLamb)
12. Re: New Cubesat - the Ultimate Fox Hunt (Joe)
13. Re: New Cubesat - the Ultimate Fox Hunt (Bob Bruninga )
14. Re: New Cubesat - the Ultimate Fox Hunt (Joe)
----------------------------------------------------------------------
Message: 1
Date: Sun, 9 Aug 2009 15:16:04 -0400 (EDT)
From: "Bob Bruninga " <bruninga@xxxx.xxx>
Subject: [amsat-bb] New Cubesat - the Ultimate Fox Hunt
To: amsat-bb@xxxxx.xxx
Message-ID: <20090809151604.AAL60418@xxxxx.xxxx.xxx>
Content-Type: text/plain; charset=us-ascii
One university at this year's Utah Cubesat Workshop, is designing a re-entry
cubesat.
Talk about the ultimate ham radio fox hunt! Find this pebble somewhere over a
few million square miles...
The problem is having a transmitter to survive the re-entry... One figure is
that about 300 Killowatt Hours of energy has to be disipated in a few minutes.
Why is it that all re-entries always end in the ball of fire over just a few
minutes. Why cannot the re-enetry energy be disipated over a longer period to
make it more survivable. Of course, if they could, they would. It appears to
be the nature of the beast. You are entering an ever denser medium, so the
drag has to escallate and you end up with the 6/7 minute burn.
What if the surface of the re-entry vehicle radically changed during the re-
entry phase? As the density of the atomosphere increased, the surface area
decreases. An ablative system that instead of burning off a thin skin of
material as in most re-entry systems, you planned on burning off 95% of the
original drag volume? What re-entry profile could be achieved Could we make
a golfball core "pinger" that could survive?
With the cheap $8k launches and only 3 month mission life, this idea of
concentrating on making an interesting mission at the re-entry phase is a new
opportunity..
The ultimate fox hunt?
Bob, WB4APR
------------------------------
Message: 2
Date: Sun, 9 Aug 2009 15:19:23 -0400
From: Norman W Osborne <ve3cje@xxxxx.xxx>
Subject: [amsat-bb] FT-736r com port settings.
To: amsat-bb <AMSAT-BB@xxxxx.xxx>
Message-ID:
<4fa78c6b0908091219p5b0e841eq7de3872a2668365d@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
Hello everyone,
Could some one tell me the com port settings for cat control of the FT-736r.
Can't seem to find the settings for the computer, I believe it is 4800 baud
but not
sure about the rest of the settings..
Norman.
------------------------------
Message: 3
Date: Sun, 09 Aug 2009 14:40:34 -0500
From: Joe <nss@xxx.xxx>
Subject: [amsat-bb] Re: New Cubesat - the Ultimate Fox Hunt
To: Bob Bruninga <bruninga@xxxx.xxx>
Cc: amsat-bb@xxxxx.xxx
Message-ID: <4A7F2632.10304@xxx.xxx>
Content-Type: text/plain; charset=us-ascii; format=flowed
Ok, Say can anyone find me this info?
The shuttle average orbital speed is 17580 MPh.
So launch starts at zero, and ends up at 17580
then coming back down goes from 17580 to zero.
Ok, Now what I want is,,
At Time = zero it's zero MPH, at t+1 min it's now at what altitude,
and what speed?
at T+2 min alt and speed?
at T+3 in alt and speed
continue all the way to orbit.
Now do it the other way, at time od de orbit burn it's at what
altitude and 17580 MPh,
at t+ 1 min after burn it;'s at alt and speed,
etc, all the way til it has landed,
does anyone have this information?
Joe
Bob Bruninga wrote:
>One university at this year's Utah Cubesat Workshop, is designing a re-entry
cubesat.
>
>Talk about the ultimate ham radio fox hunt! Find this pebble somewhere over
a few million square miles...
>
>The problem is having a transmitter to survive the re-entry... One figure is
that about 300 Killowatt Hours of energy has to be disipated in a few minutes.
>
>Why is it that all re-entries always end in the ball of fire over just a few
minutes. Why cannot the re-enetry energy be disipated over a longer period to
make it more survivable. Of course, if they could, they would. It appears to
be the nature of the beast. You are entering an ever denser medium, so the
drag has to escallate and you end up with the 6/7 minute burn.
>
>What if the surface of the re-entry vehicle radically changed during the re-
entry phase? As the density of the atomosphere increased, the surface area
decreases. An ablative system that instead of burning off a thin skin of
material as in most re-entry systems, you planned on burning off 95% of the
original drag volume? What re-entry profile could be achieved Could we make
a golfball core "pinger" that could survive?
>
>With the cheap $8k launches and only 3 month mission life, this idea of
concentrating on making an interesting mission at the re-entry phase is a new
opportunity..
>
>The ultimate fox hunt?
>
>Bob, WB4APR
>_______________________________________________
>Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
>Not an AMSAT-NA member? Join now to support the amateur satellite program!
>Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
>
>
>------------------------------------------------------------------------
>
>
>No virus found in this incoming message.
>Checked by AVG - www.avg.com
>Version: 8.5.406 / Virus Database: 270.13.48/2292 - Release Date: 08/09/09
08:08:00
>
>
>
------------------------------
Message: 4
Date: Sun, 9 Aug 2009 15:07:40 -0700
From: "Greg D." <ko6th_greg@xxxxxxx.xxx>
Subject: [amsat-bb] Re: FT-736r com port settings.
To: <ve3cje@xxxxx.xxx>, <amsat-bb@xxxxx.xxx>
Message-ID: <BLU133-W26ADBFB3CCF45FE745ADC4A9090@xxx.xxx>
Content-Type: text/plain; charset="Windows-1252"
Hi Norman,
According to my manual, it's 4800bps, 8 bits, no parity, and 2 stop bits.
Greg KO6TH
> Date: Sun, 9 Aug 2009 15:19:23 -0400
> From: ve3cje@xxxxx.xxx
> To: AMSAT-BB@xxxxx.xxx
> Subject: [amsat-bb] FT-736r com port settings.
>
> Hello everyone,
>
> Could some one tell me the com port settings for cat control of the FT-736r.
> Can't seem to find the settings for the computer, I believe it is 4800 baud
> but not
> sure about the rest of the settings..
>
> Norman.
> _______________________________________________
> Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
_________________________________________________________________
Windows Live?: Keep your life in sync.
http://windowslive.com/explore?ocid=PID23384::T:WLMTAGL:ON:WL:en-
US:NF_BR_sync:082009
------------------------------
Message: 5
Date: Sun, 9 Aug 2009 15:32:27 -0700 (PDT)
From: "Patrick STODDARD \(WD9EWK/VA7EWK\)" <amsat-bb@xxxxxx.xxx>
Subject: [amsat-bb] WD9EWK from DM54/DM55 - report
To: amsat-bb@xxxxx.xxx
Message-ID: <486671.5701.qm@xxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=us-ascii
Hi!
Yesterday's road trip out to DM54/DM55 had been on my mind since my
July 2008 road trip around northern Arizona. I have worked from most
of the Arizona grids, and had thought I would need to make a multi-
day road trip along the Arizona/New Mexico border to reach these two
grids. After lots of looking at maps, I found a couple of spots near
the I-40 freeway in eastern Arizona that could be reached in a day-
trip from Phoenix. I e-mailed a few people, asking if they needed
either grid (or both) and if they were available to be on the radio
if I went out there. Things fell in place, leading to yesterday's
558.8-mile/899km road trip.
After spending some time this morning transferring the QSOs from my
mini-logbook to my log spreadsheet, I saw that I made a total of 69
QSOs. I worked 4 passes from the DM54bx/DM55ba grid boundary (2
AO-27 passes, 1 pass each on AO-51 and SO-50), and one shallow AO-51
pass from a location northeast of the grid boundary in grid DM55ba.
The location that was not on the grid boundary was a different sort
of boundary - the line between Navajo and Apache counties. There
were 56 QSOs made at the grid boundary, and 13 more from the county
line.
For all of these passes, I used my normal FM-satellite setup when
I do these road trips - Icom IC-2720H 2m/70cm FM mobile transceiver,
Elk Antennas handheld 2m/70cm log periodic, Sony ICD-P620 digital
audio recorder. I had another mobile radio as a backup (Yaesu
FT-8800R) as well as assorted HTs I could have used in case of a
problem with the IC-2720H.
Here's a summary of activities from the two locations...
*****
east of Goodwater, Arizona, along old US-66 east of I-40 exit 303 in
Navajo County (grids DM54bx and DM55ba)
35 0.000 N 109 53.745 W
In recent weeks, I had identified this area as the easiest way to
work from DM54/DM55 in a day-trip. This area is approximately 50
miles/80km west of the Arizona/New Mexico border, where there is a
portion of the old US-66 highway next to the I-40 freeway. I was
able to park at an Indian trading post to be on this grid boundary.
This part of Arizona is on a plateau, a desert without cactus, but
this particular spot is lower than the surrounding area. Except for
shallow passes to the east or west (below 10 degrees elevation), it
worked well.
Once I parked and took the photos to establish my location, I waited
for the first of two AO-27 passes at 2046 UTC. This old satellite
has been performing well lately, and this was a busy pass covering
almost all of North America while the repeater was on. I was able to
work 21 stations during this pass, so I guess there was some interest
in this location. :-) The second AO-27 pass to the west at 2226 UTC
was not as crowded, with 8 more QSOs going into the log. This pass
was the only time I worked a Canadian station at DM54/DM55 (VA6BMJ).
Later in the afternoon, I worked two more passes from this spot - an
AO-51 pass at 0042 UTC, followed by an SO-50 pass at 0137 UTC. The
AO-51 pass was a very high pass, with maximum elevation of 75 degrees
at that location. Other than a 3-minute span just after the midpoint
of the pass when I could not hear myself through the satellite, this
was another good pass - 17 more QSOs, with stations from all over the
US and a couple of Mexicans. SO-50 at 0137 UTC put 10 more QSOs in
the log, with more stations across the US plus a Mexican station.
This made a total of 56 QSOs logged at the DM54bx/DM55ba grid
boundary, not bad for a handful of passes during a single afternoon.
I had mentioned before the trip that I might try working an earlier
AO-51 pass from this spot. Had I stayed here, I would not have had
a chance to see/hear the satellite, due to the local surroundings.
That's why I moved up the road a few miles/km for that pass, and I
apologize if that meant some of you were not able to work both of
these grids while I was out there. There will be other trips I can
make to this area, now that I know of a quick way to get to DM54 when
there is no snow in northern or eastern Arizona.
*****
Navajo/Apache county line in eastern Arizona, along old US-66 3.4
miles/5.5km east of I-40 exit 303 (grid DM55ba)
35 1.122 N 109 50.694 W
Between the two AO-27 passes, I drove around the area to find a spot
where I could possibly attempt a 7-degree AO-51 pass at 2306 UTC.
This location was northeast of the grid-boundary spot, with a nice
clear view down to the horizon toward the northeast - where AO-51
would be. Since the grid-boundary spot was not a location I could
have tried a shallow pass, I had a choice.... move to a better spot,
or take a long break between the last AO-27 pass and the high AO-51
pass around 0042 UTC. Not wanting to lose a chance to make QSOs and
give out at least one of these two grids, I went down the road for
this pass.
The county line was at a cattle guard on the road. I found a marker
on one side of the road that appeared to mark the county line, and
saw the signs on each side of the cattle guard announcing the county
names. I took a series of pictures of the area including where I
parked my truck, along with pictures of my GPS receiver's display.
Once I did all of that, I drove away until just before the AO-51
pass.
A couple of minutes before the start of the pass, I drove back onto
the cattle guard and set up my station. I was surprised at how soon
into the pass I could hear the AO-51 downlink. The increased power
made a difference! I was able to work several minutes of the pass,
logging 13 QSOs. A better way to spend that time, instead of driving
to a nearby truck stop for an early dinner (I did that later).
*****
It was nice to have the additional power on the AO-51 downlink. That
helped me with the shallow pass at 2306 UTC, where I heard it earlier
than on a similar pass last month up in Utah. AO-27 has been working
well, and I had no problems on the SO-50 pass I worked up there. I
did not stay out there for the later passes on AO-51 and SO-50, since
I would have had to find another location with a better view to the
west for a 9-degree AO-51 pass. The 3.5-hour drive home was also on
my mind. There will be other times I head out there, now that I have
a nice spot where I can park and be off the road at the DM54/DM55
grid boundary.
I am printing QSL cards for yesterday's trip now, and those cards -
along with other cards from my road trip last month - will start
going to the post office tomorrow. If you worked me yesterday and
want to receive a QSL card for any QSOs, please e-mail me directly
with the information for each QSO. If you're in my log, I will send
the card(s) for those QSO(s).
Thanks to AMSAT's AO-51 Operations Group for having another weekend
on AO-51 with a V/U voice repeater mode, as well as for the increased
power on the 435.300 MHz downlink. As K8YSE mentioned in a recent
post to the -BB, stations on the FM satellites from unusual/rare
locations draw more activity to these passes. And, as always, thanks
to all the stations who made contacts with WD9EWK yesterday.
73!
Patrick WD9EWK/VA7EWK
http://www.wd9ewk.net/
------------------------------
Message: 6
Date: Sun, 09 Aug 2009 23:01:36 +0000
From: Nigel Gunn G8IFF/W8IFF <nigel@xxxxx.xxx>
Subject: [amsat-bb] keps
To: AMSAT-BB BBs <amsat-bb@xxxxx.xxx>
Message-ID: <4A7F5550.3020105@xxxxx.xxx>
Content-Type: text/plain; charset=UTF-8; format=flowed
DRAGONSAT
1 35690U 09038B 09220.88464294 +.00022194 +00000-0 +11580-3 0 00134
2 35690 051.6412 035.7633 0005116 115.3898 244.7640 15.80804251001483
ANDE DEB (POLLUX CYLIN)
1 35691U 09038C 09220.63328729 +.00034233 +00000-0 +17771-3 0 00102
2 35691 051.6393 037.0865 0003255 069.0477 291.1106 15.80656066001419
ANDE DEB (CASTOR CYLIN)
1 35692U 09038D 09220.56928116 .00061066 00000-0 30812-3 0 128
2 35692 051.6392 037.4098 0003437 055.7583 304.4121 15.81012975 1403
ANDE POLLUX SPHERE
1 35693U 09038E 09220.69780859 +.00019858 +00000-0 +10642-3 0 00113
2 35693 051.6403 036.7728 0003745 062.1691 297.9845 15.80308849001421
ANDE CASTOR SPHERE
1 35694U 09038F 09220.69892186 +.00010960 +00000-0 +61154-4 0 00122
2 35694 051.6414 036.7818 0004427 064.7435 295.4090 15.80038418001423
ANDE DEB (AVIONICS DECK)
1 35695U 09038G 09220.63530312 +.00026048 +00000-0 +13883-3 0 00115
2 35695 051.6410 037.1071 0004454 066.2379 293.9201 15.80230919001416
--
Nigel A. Gunn, 1865 El Camino Drive, Xenia, OH 45385-1115, USA. tel +1 937
825 5032
Amateur Radio G8IFF W8IFF (was KC8NHF), e-mail nigel@xxxxx.xxx www
http://www.ngunn.net
Member of ARRL, GQRP #11396, QRPARCI #11644, SOC #548, Flying Pigs QRP Club
International #385,
Dayton ARA #2128, AMSAT-NA LM-1691, AMSAT-UK 0182, MKARS, ALC,
GCARES, XWARN.
------------------------------
Message: 7
Date: Sun, 9 Aug 2009 19:31:19 EDT
From: G0MRF@xxx.xxx
Subject: [amsat-bb] Re: New Cubesat - the Ultimate Fox Hunt
To: bruninga@xxxx.xxx
Cc: amsat-bb@xxxxx.xxx
Message-ID: <d5e.54945df4.37b0b647@xxx.xxx>
Content-Type: text/plain; charset="US-ASCII"
In a message dated 09/08/2009 19:42:06 GMT Standard Time, nss@xxx.xxx
writes:
Why is it that all re-entries always end in the ball of fire over just a
few minutes. Why cannot the re-enetry energy be disipated over a longer
period to make it more survivable. Of course, if they could, they would. It
appears to be the nature of the beast. You are entering an ever denser
medium, so the drag has to escallate and you end up with the 6/7 minute burn.
>
>What if the surface of the re-entry vehicle radically changed during the
re-entry phase? As the density of the atomosphere increased, the surface
area decreases. An ablative system that instead of burning off a thin skin
of material as in most re-entry systems, you planned on burning off 95% of
the original drag volume? What re-entry profile could be achieved Could
we make a golfball core "pinger" that could survive?
Or, the not so 'cube'sat structure is an aerodynamic shape made from a cast
ceramic material which glides in at a shallow angle allowing the energy to
be dissipated over a much longer period of time.
OK the solar cells burn off but an internal antenna would be OK as ceramics
are fairly transparent to RF and a battery would provide the final hour or
so of tlm.
Would love to see the temp readings as it comes down.
Would not love to be on the final end of the trajectory when it arrives.
David G0MRF
------------------------------
Message: 8
Date: Sun, 09 Aug 2009 18:47:21 -0500
From: Joe <nss@xxx.xxx>
Subject: [amsat-bb] Re: New Cubesat - the Ultimate Fox Hunt
To: G0MRF@xxx.xxx
Cc: amsat-bb@xxxxx.xxx
Message-ID: <4A7F6009.6060808@xxx.xxx>
Content-Type: text/plain; charset=us-ascii; format=flowed
Exactly David,
This was my reasoning for trying to get the data I asked for in a
earlier message.
I have been asking this for Years and No one EVER has been able to give
me this info.
if i was a conspiracy guy i'd be in the boat with the moon landing guys
that orbital space travel doesn't happen. Or at least manned never has
happened,
But i'm not. but i am frustrated that the speed vs altitude at take
off and re entry sseems to be totally un available.
because look at that
at take off we go from zero to 17580 Mph in what 10 minutes or so and
are in orbit.
Yet the other way around gouing from 1780 to zero on 45 minutes causes
the fireball effect with the friction.
Why not on the way up?
Thats what i want to be able ro read on the way up when it's at 60K feet
it's moving at what speed, as wellas on the way down also,
and every other possible altitude,
I want to compare speeds at all altitudes.
we can go from zero to 17580 in ten min on the way up with no fireball,
but take a slower, 450% slower return rate and it almost fries to a crisp.
Huh?
Joe WB9SBD
G0MRF@xxx.xxx wrote:
>
>
>
>Or, the not so 'cube'sat structure is an aerodynamic shape made from a cast
> ceramic material which glides in at a shallow angle allowing the energy to
>be dissipated over a much longer period of time.
>OK the solar cells burn off but an internal antenna would be OK as ceramics
> are fairly transparent to RF and a battery would provide the final hour or
>so of tlm.
>Would love to see the temp readings as it comes down.
>Would not love to be on the final end of the trajectory when it arrives.
>
>David G0MRF
>
>_______________________________________________
>Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
>Not an AMSAT-NA member? Join now to support the amateur satellite program!
>Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
>
>
>------------------------------------------------------------------------
>
>
>No virus found in this incoming message.
>Checked by AVG - www.avg.com
>Version: 8.5.406 / Virus Database: 270.13.48/2292 - Release Date: 08/09/09
08:08:00
>
>
>
------------------------------
Message: 9
Date: Sun, 9 Aug 2009 16:51:54 -0700 (PDT)
From: Jim Jerzycke <kq6ea@xxxxxxx.xxx>
Subject: [amsat-bb] Re: New Cubesat - the Ultimate Fox Hunt
To: bruninga@xxxx.xxxx G0MRF@xxx.xxx
Cc: amsat-bb@xxxxx.xxx
Message-ID: <149806.78413.qm@xxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=iso-8859-1
Yeah, it might wind up being a super-sonic "Lawn Dart"!
Jim? KQ6EA
--- On Sun, 8/9/09, G0MRF@xxx.xxx <G0MRF@xxx.xxx> wrote:
From: G0MRF@xxx.xxx <G0MRF@xxx.xxx>
Subject: [amsat-bb] Re: New Cubesat - the Ultimate Fox Hunt
To: bruninga@xxxx.xxx
Cc: amsat-bb@xxxxx.xxx
Date: Sunday, August 9, 2009, 4:31 PM
In a message dated 09/08/2009 19:42:06 GMT Standard Time, nss@xxx.xxxx
writes:
Why is? it that all re-entries always end in the ball of fire over just a
few? minutes.? Why cannot the re-enetry energy be disipated over a longer?
period to make it more survivable.? Of course, if they could, they? would.? It
appears to be the nature of the beast. You are entering an? ever denser
medium, so the drag has to escallate and you end up with the 6/7? minute burn.
>
>What if the surface of the re-entry vehicle? radically changed during the
re-entry phase?? As the density of the? atomosphere increased, the surface
area decreases.? An ablative system? that instead of burning off a thin skin
of material as in most re-entry? systems, you planned on burning off 95% of
the original drag volume????What re-entry profile could be achieved? Could
we make a golfball core? "pinger" that could survive?
Or, the not so 'cube'sat structure is an aerodynamic shape made from a cast
ceramic material which glides in at a shallow angle allowing the energy to
be? dissipated over a much longer period of time.
OK the solar cells burn off but an internal antenna would be OK as ceramics
are fairly transparent to RF and a battery would provide the final hour or
so of? tlm.
Would love to see the temp readings as it comes down.
Would not love to be on the final end of the trajectory when it? arrives.
David???G0MRF
_______________________________________________
Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
Not an AMSAT-NA member? Join now to support the amateur satellite program!
Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 10
Date: Sun, 9 Aug 2009 17:32:13 -0700 (PDT)
From: Pete Rowe <ptrowe@xxxxx.xxx>
Subject: [amsat-bb] Re: New Cubesat - the Ultimate Fox Hunt
To: G0MRF@xxx.xxxx Joe <nss@xxx.xxx>
Cc: amsat-bb@xxxxx.xxx
Message-ID: <373524.13053.qm@xxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=iso-8859-1
Hi Joe
Check out this URL:
http://www.aerospaceweb.org/question/spacecraft/q0183.shtml
There is a table that shows the speed versus altitude for a shuttle launch. I
think the key thing is that while it is in the thick part of the atmosphere (
I believe below 60k feet) the shuttle is going fairly slowly. It doesn't
really get going until it is clear of the atmosphere.
I'm just guessing that on the return trip it is still going very fast when it
gets to the thick atmosphere and hence, since there is nothing to slow it down
except the atmosphere, it gets very hot.
Does this make sense?
73,
Pete
WA6WOA
--- On Sun, 8/9/09, Joe <nss@xxx.xxx> wrote:
From: Joe <nss@xxx.xxx>
Subject: [amsat-bb] Re: New Cubesat - the Ultimate Fox Hunt
To: G0MRF@xxx.xxx
Cc: amsat-bb@xxxxx.xxx
Date: Sunday, August 9, 2009, 4:47 PM
Exactly David,
This was my reasoning for trying to get the data I asked for in a
earlier message.
I have been asking this for Years and No one EVER has been able to give
me this info.
if i was a conspiracy guy i'd be in the boat with the moon landing guys
that orbital space travel doesn't happen.? Or at least manned never has
happened,
But i'm not.? but i am frustrated that the speed vs altitude at take
off? and re entry sseems to be totally un available.
because look at that
at take off we go from zero to 17580 Mph in what 10 minutes or so and
are in orbit.
Yet the other way around gouing from 1780 to zero on 45 minutes? causes
the fireball effect with the friction.
Why not on the way up?
Thats what i want to be able ro read on the way up when it's at 60K feet
it's moving at what speed,? as wellas on the way down also,
and every other possible altitude,
I want to compare speeds at all altitudes.
we can go from zero to 17580 in ten min on the way up with no fireball,?
but take a slower,? 450% slower return rate and it almost fries to a crisp.
Huh?
Joe WB9SBD
G0MRF@xxx.xxx wrote:
>
>
>
>Or, the not so 'cube'sat structure is an aerodynamic shape made from a cast
> ceramic material which glides in at a shallow angle allowing the energy to
>be? dissipated over a much longer period of time.
>OK the solar cells burn off but an internal antenna would be OK as ceramics
> are fairly transparent to RF and a battery would provide the final hour or
>so of? tlm.
>Would love to see the temp readings as it comes down.
>Would not love to be on the final end of the trajectory when it? arrives.
>
>David???G0MRF
>
>_______________________________________________
>Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
>Not an AMSAT-NA member? Join now to support the amateur satellite program!
>Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
>?
>
>------------------------------------------------------------------------
>
>
>No virus found in this incoming message.
>Checked by AVG - www.avg.com
>Version: 8.5.406 / Virus Database: 270.13.48/2292 - Release Date: 08/09/09
08:08:00
>
>?
>
_______________________________________________
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------------------------------
Message: 11
Date: Sun, 9 Aug 2009 21:14:04 -0400
From: Lee McLamb <ku4os@xxx.xx.xxx>
Subject: [amsat-bb] Re: New Cubesat - the Ultimate Fox Hunt
To: amsat-bb@xxxxx.xxx
Message-ID: <200908092114.05145.ku4os@xxx.xx.xxx>
Content-Type: Text/Plain; charset="iso-8859-1"
In the case of Delta II second stage tanks some analysis concluded that what
allows them to survive reenty is that a hole initially burns in one end which
results in a shape that creates a shockwave. The shockwave then deflects most
of the heat around the tank.
Some pictures if you're curious.
http://orbitaldebris.jsc.nasa.gov/reentry/recovered.html
Probably hard to implement on a sub-nanosat scale but suggests another
approach.
Lee
On Sunday 09 August 2009 15:16:04 Bob Bruninga wrote:
> What if the surface of the re-entry vehicle radically changed during the
> re-entry phase? As the density of the atomosphere increased, the surface
> area decreases. An ablative system that instead of burning off a thin skin
> of material as in most re-entry systems, you planned on burning off 95% of
> the original drag volume? What re-entry profile could be achieved Could
> we make a golfball core "pinger" that could survive?
>
> With the cheap $8k launches and only 3 month mission life, this idea of
> concentrating on making an interesting mission at the re-entry phase is a
> new opportunity..
>
> The ultimate fox hunt?
>
> Bob, WB4APR
> _______________________________________________
> Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
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------------------------------
Message: 12
Date: Sun, 09 Aug 2009 20:30:02 -0500
From: Joe <nss@xxx.xxx>
Subject: [amsat-bb] Re: New Cubesat - the Ultimate Fox Hunt
To: Pete Rowe <ptrowe@xxxxx.xxx>
Cc: amsat-bb@xxxxx.xxx
Message-ID: <4A7F781A.5070309@xxx.xxx>
Content-Type: text/plain; charset=us-ascii; format=flowed
Ok we have half the numbers, This I also have gotten before a LOT, but
coming back down, is no place. I want tosee these numbers.
Pete Rowe wrote:
>Hi Joe
>Check out this URL:
>http://www.aerospaceweb.org/question/spacecraft/q0183.shtml
>
>There is a table that shows the speed versus altitude for a shuttle launch. I
think the key thing is that while it is in the thick part of the atmosphere (
I believe below 60k feet) the shuttle is going fairly slowly. It doesn't
really get going until it is clear of the atmosphere.
>
>I'm just guessing that on the return trip it is still going very fast when it
gets to the thick atmosphere and hence, since there is nothing to slow it down
except the atmosphere, it gets very hot.
>Does this make sense?
>
>73,
>Pete
>WA6WOA
>
>--- On Sun, 8/9/09, Joe <nss@xxx.xxx> wrote:
>
>From: Joe <nss@xxx.xxx>
>Subject: [amsat-bb] Re: New Cubesat - the Ultimate Fox Hunt
>To: G0MRF@xxx.xxx
>Cc: amsat-bb@xxxxx.xxx
>Date: Sunday, August 9, 2009, 4:47 PM
>
>Exactly David,
>
>This was my reasoning for trying to get the data I asked for in a
>earlier message.
>
>I have been asking this for Years and No one EVER has been able to give
>me this info.
>
>if i was a conspiracy guy i'd be in the boat with the moon landing guys
>that orbital space travel doesn't happen. Or at least manned never has
>happened,
>
>But i'm not. but i am frustrated that the speed vs altitude at take
>off and re entry sseems to be totally un available.
>
>because look at that
>
>at take off we go from zero to 17580 Mph in what 10 minutes or so and
>are in orbit.
>
>Yet the other way around gouing from 1780 to zero on 45 minutes causes
>the fireball effect with the friction.
>
>Why not on the way up?
>
>Thats what i want to be able ro read on the way up when it's at 60K feet
>it's moving at what speed, as wellas on the way down also,
>
>and every other possible altitude,
>
>I want to compare speeds at all altitudes.
>
>we can go from zero to 17580 in ten min on the way up with no fireball,
>but take a slower, 450% slower return rate and it almost fries to a crisp.
>
>Huh?
>
>Joe WB9SBD
>
>G0MRF@xxx.xxx wrote:
>
>
>
>>
>>Or, the not so 'cube'sat structure is an aerodynamic shape made from a cast
>>ceramic material which glides in at a shallow angle allowing the energy to
>>be dissipated over a much longer period of time.
>>OK the solar cells burn off but an internal antenna would be OK as ceramics
>>are fairly transparent to RF and a battery would provide the final hour or
>>so of tlm.
>>Would love to see the temp readings as it comes down.
>>Would not love to be on the final end of the trajectory when it arrives.
>>
>>David G0MRF
>>
>>_______________________________________________
>>Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
>>Not an AMSAT-NA member? Join now to support the amateur satellite program!
>>Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
>>
>>
>>------------------------------------------------------------------------
>>
>>
>>No virus found in this incoming message.
>>Checked by AVG - www.avg.com
>>Version: 8.5.406 / Virus Database: 270.13.48/2292 - Release Date: 08/09/09
08:08:00
>>
>>
>>
>>
>>
>_______________________________________________
>Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
>Not an AMSAT-NA member? Join now to support the amateur satellite program!
>Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
>
>
>
>
>_______________________________________________
>Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
>Not an AMSAT-NA member? Join now to support the amateur satellite program!
>Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
>
>
>------------------------------------------------------------------------
>
>
>No virus found in this incoming message.
>Checked by AVG - www.avg.com
>Version: 8.5.406 / Virus Database: 270.13.49/2293 - Release Date: 08/09/09
18:10:00
>
>
>
------------------------------
Message: 13
Date: Sun, 9 Aug 2009 21:58:34 -0400 (EDT)
From: "Bob Bruninga " <bruninga@xxxx.xxx>
Subject: [amsat-bb] Re: New Cubesat - the Ultimate Fox Hunt
To: "Joe" <nss@xxx.xxx>, G0MRF@xxx.xxx
Cc: amsat-bb@xxxxx.xxx
Message-ID: <20090809215834.AAL62158@xxxxx.xxxx.xxx>
Content-Type: text/plain; charset=us-ascii
> at take off we go from zero to 17580 Mph
> in what 10 minutes or so and are in orbit.
> Yet the other way around going from 1780
> to zero in 45 minutes causes the fireball
> effect with the friction.
>
> Why not on the way up?
It does, its just that all the energy is being burned at the rear end of the
rocket to produce the acceleration... see the flames... On the way down, you
have to decelerate that same amount of acceleration in the opposite direction
and remove all that LAUNCH energy, to come back down.... hence the flames.
The difference is that going up, you are going slowly in the higher density
atmosphere which is continually lessening as you go up letting you go faster
and faster with less and less friction. THus, no multiplying build up of
friction.
Coming down, everything is against you. As you come down, into denser and
denser atmosphere, the friction is increasing and increasing, the temperature
building and building you are going slower and slower and falling faster and
faster. Into one ultimate fireball.
> we can go from zero to 17580 in ten min
> on the way up with no fireball, but take
> a slower, 450% slower return rate and it
> almost fries to a crisp.
Thats why I'm thinking there might be a way to change your drag coefficient as
you come down to reduce the crescendo build up of heat and spread out the
descent. But still, for something as small as a cubesat you still have to
disipate about 300KWH of energy and even if you do this over an hour, thats
still 300 killowatts of heat... (a number they used here in the presentation..
I'd like to see confirmation)...
Still seems like a fireball..
Bob, WB4APR
------------------------------
Message: 14
Date: Sun, 09 Aug 2009 21:08:31 -0500
From: Joe <nss@xxx.xxx>
Subject: [amsat-bb] Re: New Cubesat - the Ultimate Fox Hunt
To: Pete Rowe <ptrowe@xxxxx.xxx>
Cc: amsat-bb@xxxxx.xxx
Message-ID: <4A7F811F.6020303@xxx.xxx>
Content-Type: text/plain; charset=us-ascii; format=flowed
Yes this does make all the sence in the world, but why tho can no one
find true actual data as this IS exactly what's hhappening?
I can find hundreds of pages a of data on the way up but not one single
one for data onthe way down, That I would love to see.
Pete Rowe wrote:
>Hi Joe
>Check out this URL:
>http://www.aerospaceweb.org/question/spacecraft/q0183.shtml
>
>There is a table that shows the speed versus altitude for a shuttle launch. I
think the key thing is that while it is in the thick part of the atmosphere (
I believe below 60k feet) the shuttle is going fairly slowly. It doesn't
really get going until it is clear of the atmosphere.
>
>I'm just guessing that on the return trip it is still going very fast when it
gets to the thick atmosphere and hence, since there is nothing to slow it down
except the atmosphere, it gets very hot.
>Does this make sense?
>
>73,
>Pete
>WA6WOA
>
>--- On Sun, 8/9/09, Joe <nss@xxx.xxx> wrote:
>
>From: Joe <nss@xxx.xxx>
>Subject: [amsat-bb] Re: New Cubesat - the Ultimate Fox Hunt
>To: G0MRF@xxx.xxx
>Cc: amsat-bb@xxxxx.xxx
>Date: Sunday, August 9, 2009, 4:47 PM
>
>Exactly David,
>
>This was my reasoning for trying to get the data I asked for in a
>earlier message.
>
>I have been asking this for Years and No one EVER has been able to give
>me this info.
>
>if i was a conspiracy guy i'd be in the boat with the moon landing guys
>that orbital space travel doesn't happen. Or at least manned never has
>happened,
>
>But i'm not. but i am frustrated that the speed vs altitude at take
>off and re entry sseems to be totally un available.
>
>because look at that
>
>at take off we go from zero to 17580 Mph in what 10 minutes or so and
>are in orbit.
>
>Yet the other way around gouing from 1780 to zero on 45 minutes causes
>the fireball effect with the friction.
>
>Why not on the way up?
>
>Thats what i want to be able ro read on the way up when it's at 60K feet
>it's moving at what speed, as wellas on the way down also,
>
>and every other possible altitude,
>
>I want to compare speeds at all altitudes.
>
>we can go from zero to 17580 in ten min on the way up with no fireball,
>but take a slower, 450% slower return rate and it almost fries to a crisp.
>
>Huh?
>
>Joe WB9SBD
>
>G0MRF@xxx.xxx wrote:
>
>
>
>>
>>Or, the not so 'cube'sat structure is an aerodynamic shape made from a cast
>>ceramic material which glides in at a shallow angle allowing the energy to
>>be dissipated over a much longer period of time.
>>OK the solar cells burn off but an internal antenna would be OK as ceramics
>>are fairly transparent to RF and a battery would provide the final hour or
>>so of tlm.
>>Would love to see the temp readings as it comes down.
>>Would not love to be on the final end of the trajectory when it arrives.
>>
>>David G0MRF
>>
>>_______________________________________________
>>Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
>>Not an AMSAT-NA member? Join now to support the amateur satellite program!
>>Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
>>
>>
>>------------------------------------------------------------------------
>>
>>
>>No virus found in this incoming message.
>>Checked by AVG - www.avg.com
>>Version: 8.5.406 / Virus Database: 270.13.48/2292 - Release Date: 08/09/09
08:08:00
>>
>>
>>
>>
>>
>_______________________________________________
>Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
>Not an AMSAT-NA member? Join now to support the amateur satellite program!
>Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
>
>
>
>
>_______________________________________________
>Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
>Not an AMSAT-NA member? Join now to support the amateur satellite program!
>Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
>
>
>------------------------------------------------------------------------
>
>
>No virus found in this incoming message.
>Checked by AVG - www.avg.com
>Version: 8.5.406 / Virus Database: 270.13.49/2293 - Release Date: 08/09/09
18:10:00
>
>
>
------------------------------
_______________________________________________
Sent via amsat-bb@xxxxx.xxx. Opinions expressed are those of the author.
Not an AMSAT member? Join now to support the amateur satellite program!
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