STRATOSPHERE ONLINE

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This is an electronic version of a special edition of the "Stratosphere" Newsletter that we hand out to participants of events we attend. It is periodically edited to highlight some current activity. In this version of the Membership Edition, we place the spotlight on these WWW Pages.

Several articles contained in this newsletter are also posted here in our "About EOSS" section. If you wish to read those articles, click on their titles and you'll be taken to them. To return to this page select Return to Special Edition at the bottom of the article and you will be returned to the Contents below.

This is probably seems a bit strange to many of you however, I thought it might be of interest to folks who are attempting to create similar handouts for their prospective members.

CONTENTS

A Typical Flight

Pre-Flight

There probably really isn't a typical flight profile for an Edge of Space Sciences balloon launch. Several months prior to lift-off a mission flight plan is developed. This plan may be formed to test existing equipment, fly an educational experiment for a customer or run a promotional flight that is deemed of sufficient interest to the community at large to be worth the time and money invested. This mission plan is submitted to the EOSS board of directors for initial consideration. Unless the plan is completely outside of the mission goals of EOSS, the board will present the mission to the membership at our regular monthly meeting. The proponent of the plan is expected to attend the meeting and defend their proposal. Members are encouraged to examine the plan, ask questions, and question the submitter concerning any and all aspects of the mission. Once a full hearing has been held we vote on whether or not to proceed with the mission. Often at the earliest stages it is necessary to further examine the flight proposal and only preliminary approval is given pending the results of investigations into any aspects of the flight that require further consideration.

If all goes well then the flight goes on our launch schedule. When this happens, we set a tentative launch date and a time line for any and all of the various tasks that must be completed prior to launch.

During the run up to launch day many items have to be checked. Is the payload ready? Do we have a direction finding team ready to go into the field and conduct recovery operations? Are there personnel available for the launch preparation and ground station teams?

A critical design review (CDR) is held several weeks prior to launch to ensure that the payload is properly configured with any new on board experiments. If the payload passes muster and all personnel needed for the flight have committed, then we have a GO for launch.

Flight

Flight day represents the culmination of efforts. At any EOSS flight there are anywhere from 15 to hundreds of people involved in varying capacities.

The first person to rise on flight day is our weather person. It is this hardy soul's responsibility to obtain the morning's high altitude winds report. This usually involves a trip to the National Weather Service Station at Stapleton Airport. Once obtained, these wind reports are entered into the computer program BALLTRAK created by Bill Brown (WB8ELK) and used to predict the touchdown point of our payload later that day. Without this information, we would need a much larger contingent of field DF teams. BALLTRAK usually gives good predictions of the landing zone of the payload. Thus, we do not need to spread field teams around the launch site. Instead, we concentrate them in the direction of the expected touchdown.

Next to awaken, are the remaining groups involved with the flight. This usually means three teams of folks; the DF hunters, the launch team and the ground station team.

The Launch and Ground station teams move to the launch site. With them they carry all the paraphernalia required to launch and control a payload. It's quite an impressive list of equipment and it takes a knowledgeable group to move it to a location and set up for operations.

The DF teams are aware of the expected touch down location and the Field team coordinator will assign each station to a location suited to tracking of the payload. Depending on the number of hunters in the group this dispersion of teams can vary quite a bit.

An hour prior to the flight all systems should be up and running. The DF teams should be closing on their assigned positions and the balloon and its payload should be in the final stages of preparation for launch. We like to operate at least a little ahead of our time line to ensure a margin for recovery if we discover any systems that need emergency repair.

At lift-off minus 30 minutes the balloon is prepared for flight. A protective drop cloth is placed on the ground and the balloon is laid out and filled with helium. Once the desired lift factor is achieved, the balloon is sealed and the payload train (various instruments attached to a line with a parachute at the top) is firmly tied to the balloon.

Depending on the lift-off location and nature of our payload, liaison with the Federal Aviation Agency (FAA) is established to ensure a safe flight for both our payload and the pilots who may be traversing our launch and landing areas.

Final checks of all systems are made and if all goes well, the balloon is released.

Seconds after lift-off, the balloon has reached sufficient altitude for our distant tracking and recovery teams to acquire it's various signals. They relay this information to the logistics coordinator. This position is held by one of the recovery team members and is responsible for coordination of all information pertaining to the flight path and recovery of the payload.

The ground station usually has a crowd of spectators present. They are able to view, depending on our payload configuration, a live TV picture from the balloon. This is usually the big draw. Because we can pan the view of the camera up and down we can show a variety of views. We can show the balloon as it expands in the rarefied atmosphere. Pictures of the horizon which slowly assumes a curved shape due to the extreme altitude of the payload are quite interesting. The sky which starts out a normal blue (or gray with a B&W camera) and slowly fades to Black as the balloon ascends above most of the atmosphere is always a crowd pleaser. And of course, the ground views are always popular where at first details of streets are visible and later only the most major of landmarks stand out from an altitude of 16 miles in the air.

In addition to these marvelous pictures, our payloads usually carry various experiments which send down telemetry that can be viewed on various computer screens set up at the ground station. The main computer shows simple text information on the current altitude, latitude and longitude, and temperatures on board the payload. Another computer may be set up with a graphic map showing the real-time location of the balloon as determined by the telemetry being beamed down to the ground station.

The balloon ascends to the neighborhood of 100,000 feet and is either released or allowed to burst. At that time, the payload train begins its rapid descent. A parachute is deployed, however it has little effect on the descent rate until the payload is low enough for sufficient atmosphere to brake it's fall.

During the descent, the tracking and recovery teams estimate the touchdown location and refine their locations for tracking.

Soon the balloon lands and the tracking teams lose the signal. It is always hoped that someone is close enough to maintain contact once the payload has landed, however, if this does not happen, the last readings from the tracking teams are correlated and an estimated touchdown point is determined. Everyone drives toward this location listening to their receivers for some hint of the transmitters aboard the payload.

In 17 of our last 18 flights recovery has been effected in minutes to an hour or two after landing. One flight did take a detour into Nebraska leading the tracking teams on a merry chase, but that is definitely the exception.

Once recovery is effected, the balloon payload systems are returned to the launch site and experimental data is distributed to the various participating groups.

Flying to the Edge of Space is an excellent way to demonstrate to students the fun, excitement and interest that a science project can generate. Support the group with your membership and you will be furthering the science and math skills of our students today, making for a brighter future for all of us tomorrow.

 

EOSS Debuts on the Internet!!

OK, we've talked about it for months, years even. And it's finally here. EOSS now has its own home page on the internet.

There are lots of ways to make your presence known on the internet. You can start up your own full time node for thousands of bucks, and hundreds in monthly expenses. You can "rent" space on another machine for an FTP, WWW site costing big bucks too. Or, you can create a home page for "free". Well, that last one isn't exactly free. You need an account and enough disk space on that account to hold the material but once you've done that it's no extra charge.

I've been on Internet Express for the past year. I have the space. So ... I did it.

Why did it take so long?

Well, I really didn't have a good connection into the internet until recently. Previously, I had a shell account. It's much like here on the Filebank. You call a number and connect to a BBS like interface. This type of access doesn't allow for Mosaic browsers (the best way to surf the internet). Now, I've got that capability! In my case it's called PPP (Point to Point Protocol). It connects my computer DIRECTLY to the internet and I can go anywhere and see and HEAR anything that I have privileges to. Some areas do require passwords and accounts. And, thanks to Tom Isenberg's relentless exploration of his account, it was revealed that I could indeed create a home for EOSS.

How do you get there?

Well, you need at least a real internet account that offers some type of WWW browsing software. Most systems offer text based browsers on their systems. One of the most popular is "LYNX". Poke around your system and look for WWW.

The best way to get online to the EOSS Home Page is to use a fully graphic interface. To do that you need a SLIP, CSLIP or PPP account that connects your computer directly to the net.

Once you're in a browser you need to give that program an address to go look for information. The EOSS Home Page is located at:

http://www.usa.net/~rickvg/eoss.htm

note: Obviously you know it has changed to  http://www.eoss.org I just left that old reference for historical accuracy

note: Old time users may expect a file extension of html. Don't worry, this extension should work fine with all machines. It just means I created my pages on a Windows system. That character before rickvg is a tilde(~). It's located above the tab key on my keyboard. On yours ... who knows.

When you give this address to the browser you're transported across the internet to the home page located in my user area. The page is displayed on your screen. If you're using a graphic browser you'll see a title, the picture (in GIF format) on the front page of this handout, and a table of contents.

It's possible to link navigational commands to text (hypertext) in this system. So, you can point your mouse cursor (graphic system) or use your cursor control keys to "point" to hot links. Pressing a down arrow will consecutively highlight different items moving down the table of contents. Pressing the up arrow key will move the highlight back up the list. The cursor jumps to the next hotlink in the text so it may jump up a page skipping over lots of text. This is normal operation. Pressing a right arrow or hitting the enter key or mouse button 1 (usually the left button) clicking will activate that navigational link and move you to the area of interest. Where ever you move to, you can always go back at least one step to the previous location. In a text based system you hit the left arrow key. On a graphic system there's usually a "back" icon.

Well, this announcement isn't meant as an HTML primer. It's all highly intuitive. Just get in there and jump around.

I've "alpha" tested the pages with Ted Cline and Tom Isenberg. They have caught some problems I've fixed. Now I'm opening up the pages to members of EOSS. If you can use WWW, get in there and take a look. If you have any suggestions, or discover any problems, email me at webmaster@eoss.org and I'll take care of them. After a short "beta" test period, I'll make an announcement to all of EOSS's distant members on the internet and post an notice in rec.radio.amateur.misc.

That's it folks. Enjoy, and let me know what you think.