Gyroscopes are essential to aircraft instrumentation, and spacecraft orientation. This experiment shows the cadets how gyroscopes work. You’ll need a bicycle wheel and a chair which swivels. Start by explaining that a gyroscope can be any spinning object; when a force is exerted on the spinning object, it tries to turn in a direction 90° from the force applied to it. Demonstrate by having a cadet hold the bicycle wheel by the axle while you spin it. Now ask the cadet to try to turn the wheel (e.g., if the cadet is holding the axle with his/her hands straight out in front, ask him/her to try to move the hands to be top and bottom, so the wheel is parallel to the ground). The cadet will usually comment how difficult this is! (The wheel feels like it has a mind of its own.) Now ask for another cadet to volunteer. Ask this cadet to sit on the chair with his/her feet off the floor. Again, they should hold the wheel while you spin it. Now, if they try to turn the wheel, they will find themselves spinning around in the chair. Why? Because the force has been applied 90° from the direction of rotation. Now you can explain that if we had sensors on the chair that recorded how much force was making the chair turn, we could figure out how much force was applied to the wheel. Once we know force, we can calculate acceleration, and thus determine speed and position. This is how gyroscopic instruments work.
A principle which is essential for all cadets to learn is that “the faster a fluid moves, the less pressure it exerts.” People – cadets or seniors – can observe this in a shower, where the air flowing rapidly past the shower curtain makes the curtain move inward. Here’s another experiment you can do, assuming you don’t want to bring a shower to your squadron. J For this you’ll need a shop vac with an exhaust outlet on the top, and two aluminum pie tins. Cut a hole in one of the two tins that’s the same size as exhaust outlet. Turn on the vacuum, and put a piece of paper around a foot above the exhaust outlet and let go; the cadets will see that the paper flies up and away, as expected. Now place the pie tin with the hole in it over the outlet with the flanges down. (You can have a cadet hold the tin in place, or tape it down.) Now hold the other (non-mutilated) tin right-side-up and ask the cadets what will happen if you place it in the same place as you put the paper. The cadets will likely say the same thing will happen. Sure enough, the exhaust will push the tin away. But now place the non-mutilated tin very close (less than an inch away) from the other tin. Due to Bernoulli’s principle, the air between the tins will be accelerated to flow very fast, causing a drop of pressure. This will cause a suction-type of effect, and the two tins will stick together!
Bernoulli’s Principle, Take 2
Here, you take a piece of paper. Tape it down (along only one short edge only) to a table. Now carefully bend the paper into an airfoil back towards, then past, the taped edge. Take a hair dryer (the more powerful, the better) and blow it past your “wing.” The free (trailing) edge of the paper will flop upwards. Now you can take small weights (e.g., paper clips) and tape them to the trailing edge. The cadets can “bet” how many weights the wing can “lift.” The cadets can also experiment with how well different sizes and shapes of airfoils work.
This experiment shows cadets that hot air is lighter than cooler air. A really good website is http://www.balloonexplorium.org/index.php?page=tissue-paper-balloons which includes not only a template to make each gore of the balloon, but also for making a heater that you'll use to inflate (and heat) the balloon. The directions are pretty self-explanatory with the balloons. This activity really needs a weekend (or at least two separate days) to do: around 2-3 hours to put the balloons together, and another few hours to “launch” the balloons. Assuming you don’t lose the balloons, they can be re-used multiple times.
There are lots of interesting speakers in our area. If you want to incorporate history into your aerospace lecture, bring in a Tuskegee Airman, a WASP pilot, or a war veteran. Or if you want technical details about a given aerospace subject, bring in someone from one of the numerous aerospace companies in Massachusetts (or even Connecticut – e.g., Pratt & Whitney, Hamilton-Sundstrand, etc.). You can also arrange to have a speaker from one of the technical schools around (e.g., MIT, WPI, Tufts). There are lots of “specialty” pilots (e.g., hot-air-balloon, helicopter, sailplane, hang-glider, parachute) who will give talks about their flying.
There are lots of great museums around! One of the best is at Bradley Airport (Windsor Locks, CT). Try to go there on one of their many “cockpit days” they hold throughout the year – the public can then sit in the cockpit of selected aircraft! Look for the World-War-II CAP amphibious aircraft there. Another museum is at the Collings Foundation in Stow, MA. And another museum is the Goddard museum in Worcester. When planning any museum trip, it’s best if you can visit yourself ahead of time. If possible, take some pictures of the exhibits at the museum, so you can show them to the cadets before they go and explain what they’ll see. You can make up a “scavenger hunt” for the cadets to follow once they get to the museum – the hunt should include not only the exhibit they’re looking for, but also some questions they need to answer about the significance of the exhibit.
The night sky
If you have access to a telescope, there are lots of objects you can train the ‘scope on. Check out Sky and Telescope magazine (or their web site at www.skypub.com) for objects of interest. Weather Underground (www.wunderground.com) also has sky information. Jupiter and Saturn are particularly vivid for cadets. Of course, the moon is wonderful, too; it’s best viewed when it’s a quarter moon (i.e., half of the moon is visible), since the shadows will be long, allowing a good indication of mountains and deep craters. (It’s difficult to see that a mountain is there if you’re looking at it straight on.) Also, Boston University has an Observatory Open Night most Wednesdays, weather permitting – see http://www.bu.edu/dbin/astronomy/?q=AS_open.
"Gimme a cup of coffee"
This experiment teaches how fluids of different temperatures interact. (It also teaches the cadets how to play with their food! J) For this you'll need a clear mug filled with hot coffee (the hotter, the better), some cream or half-and-half, and an ice cube. Have the cadets gather around the mug closely, and s-l-o-w-l-y add the cream down the side of the mug so as not to upset the thermal balance. The cadets will observe the light-colored cream, being cold, will remain at the bottom, while the dark-colored hot coffee will be on top. Now drop an ice cube in. This upsets the thermal balance, and you'll be able to see streams of cream pushing up toward the surface, and swirling around. Typical comments from cadets: "Cool!!"
There are Control Towers, Approach-Control Facilities, and Air Route Traffic Control Centers throughout the state (or nearby). The controllers are always willing to work with us, as long as you contact them ahead of time to schedule. To contact them, look up the phone numbers in AOPA’s Aircraft USA book (ask a pilot if you don’t have this book). Boston ARTCC (actually located in Nashua, NH) is a great trip to take – cadets can not only see how the controllers direct aircraft, but they can also see how they figure out whether there will be delays in the system hours from now, and also get a lecture on meteorology.
“Pretend” Air-Traffic Controller
While we’re on the subject of air traffic control, you can give the cadets an idea of what control-tower controllers do every day. This exercise is best led by a pilot. First, write down a bunch of commands that a controller might say: taxi instructions, ATIS information, entering an airport traffic area, take-off instructions, landing instructions. Write each instruction down on an index card. Now write down similar information that a pilot might say: requests for taxi, take-off, entering the pattern, etc. (each on an index card as well). Now draw in chalk an airport diagram on the ground, including taxiways and runways. Also put some common reporting landmarks around (i.e., what landmarks around 5 miles away that pilots use when contacting a control tower for landing instructions). Now assign one cadet as a tower controller. For sake of simplicity, we’ve used only one “controller” – not distinguishing between ground and tower control. Choose a couple of cadets to be “pilots.” Take the first pilot and give him or her an index card appropriate to where he/she will be placed – e.g., a taxi card if placed on the “airport” to taxi. The “pilot” must contact the “controller” and request the action as indicated on the card, then the controller must appropriately give the proper command. Once the “pilot” has been told what to do, he or she will start to “taxi” or “fly” (as appropriate) by slowly walking the route, one foot in front of the other. Once the “controller” has gotten the hang of controlling one “pilot,” start to give him or her more and more “pilots” to control.
Air-Traffic Control, Take 2
This idea comes from Capt Malcolm Dickinson, former internal AEO for NER. Start by reading a sample ATIS and examining it part-by-part. Touch on “Zulu time,” compass headings, wind speeds, and how runways are named. Then discuss aviation radio phraseology, introducing the cadets to the standard order of information: Whom you’re calling, who you are, where you are, what information you have (optional), and what you want. You may try to try this out with more familiar material: “Cadet Baker, Cadet Smith, at home, request a ride to the meeting.” Now talk about communications with ground control, including a rough diagram of runways and taxiways on the blackboard to help illustrate “hold short” and “cross runway” clearances during taxi. Then discuss tower communications, including “hold short,” “position and hold,” and “cleared for takeoff.” Then discuss the procedures for returning to the airport; you may want to include contact with an approach controller and receiving a “squawk code” (transponder code). At the end, do a couple of “sample flights” in which the cadets tell you what happens next: what frequency to tune in, whom to talk to, what to ask for, and how to phrase the request. By the way, this can also be used for training non-pilot senior members – not just cadets!
Here the cadets can see how difficult it is to perform common tasks using “astronaut equipment.” For this you need some very heavy gloves (or ski gloves). Have the cadets try to tie a bow in a short piece of thread, or put together some tinkertoys, or… (use your imagination!). You can time how long the cadets take to do these tasks with versus without the “space gloves” on. You can also show that the rigid spacesuits can be made more maneuverable with the addition of “joints”: take a long balloon (but not too thin), and have the cadets try to bend it – it’s quite difficult. Now wrap a rubber band around the balloon to make it thinner in one spot: the balloon will now bend quite easily at that spot.
“A Chapter a Day…”
Well, maybe not a chapter a day, but every couple of months, anyway. You can take advantage of the changes in the AE program (i.e., cadets may take the AE tests in any order) by teaching a little bit of one chapter each meeting over a period of three or four months. Spend around 20 or 30 minutes each meeting.
Great Lakes region has a web site with some great ideas. Check out http://www.wpafb.af.mil/cap/glr-ae/ae.htm. Northeast Region’s AE web site has lots of good ideas (http://www.ner.cap.gov/ae/index.htm). NHQ has lots of links listed at http://www.capnhq.gov/nhq/aeroed/ETA/AE_Links.htm. Wyoming Wing created a “Jeopardy” program for each of the six Aerospace Dimensions books (http://www.capwyhq.org/drupal-5.0/?q=node/295). Of course, there’s the Aerospace Excellence “contest” that national holds: if you participate in it, they’ll send you (free!) several books containing around 30 different projects. Some of the projects aren’t very challenging (and I feel are of questionable educational value), but some are great. (Some of the above ideas are also duplicated in these books.)
Get the cadets up in the air soon, get them up often! Make sure your o-flight pilots are well versed in explaining to the cadets what they’re doing, and make sure the cadets get lots of opportunity to manipulate the controls. Also make sure you have booster cushions (so the cadets can see above the instrument panel). Advise the cadets to bring sunglasses if they have them.
The Iridium satellites are used for satellite phones (especially by the U.S. military). These satellites’ bodies are highly polished; if a satellite is in just the right orientation around sunrise or sunset, it will reflect the sun’s rays and hence appear to become phenomenally brighter – 100,000-fold or more – for a few seconds before dimming back. It is quite spectacular, and thrills young and old alike to see it! The best website for predicting flares is at www.heavens-above.com , but the site requires some instruction on how to use it:
Log onto the website, and register yourself as a new user by clicking on the “Login (optional)” link, then clicking on the “Create new user account” link. Once you have registered and logged in, click on the “Change your observation location and other settings” link. Add observing site(s) by clicking on the “add new” button and following the instructions.
Once you’ve added sites, choose the one that’s closest to where you’ll be observing. NOTE: the flares can appear dramatically different if your listed site is even a few miles different from where you are – it might even not be visible at all, so it’s important to use the most accurate site possible.
Click on the “Iridium Flares” link under Satellites. This will produce a table of flares visible over the next seven days. Look for any flare with an intensity of brighter than magnitude -6 (i.e., -7, -8, or -9). Click on the link (i.e., the date/time); this produces the star chart that shows how the satellite will be passing through the sky, and shows where the flare will occur. NOTE: this chart is meant for you to hold it above your head – that’s why West is listed on the right side and East on the left side.
The International Space Station is becoming VERY bright due to its large size. You can see it passing overhead around sunrise or sunset (sometimes even during the day!) by the same website for Iridium Flares. Fortunately, the instructions for the ISS are a bit simpler than for flares: Click on “10-day predictions for ISS” link, then click on the first column of the ISS pass you want to observe. (Note that the smaller the number in the magnitude column, the brighter the pass, so -3 is brighter than -2, etc.) You can also find the ISS passes on the NASA website http://spaceflight.nasa.gov/realdata/sightings/ .
Talk to a Satellite
Courtesy of Ken Windyka of Westover squadron: There are amateur radio low orbiting satellites that anyone licensed as a technician class amateur radio operator can access and talk to during very brief periods with just a hand held 5 watt portable radio and a consumer grade radio scanner as the receiver. Even without a license with a consumer grade radio scanner one could listen to the transmissions. See: http://www.amsat.org/amsat-new/satellites/status.php. Also, an interesting aspect about the space station is that it transmits on amateur radio frequencies of 145.80 (nfm) & 145.825 (digital packet). IF you have a regular consumer grade scanner or amateur portable radio, generally just tuning to 145.825 you will pick up the digital transmissions about 8 minutes prior to the satellite coms into view and about 5 minutes after it leaves your view. A good site for determining satellites you can view from your location is: http://www.n2yo.com/
Capt Oscar Orringer of Coastal Patrol 18 created a thorough hands-on parachute project. See "MA044 Parachute Activity Report" file below.