Scientific Ballooning • Brief history • Electrodynamics over thunderstorms • types • How a balloon works Lift (forces) USS Akron in flight, November 1931

Hindenburg Disaster: Graf https://www.youtube.com/watch?v= Zeppelin 8V5KXgFLia4 Regular transatlantic service in 1930s January 2005 MINIS Flight From SANAE Antarctica

More pictures fromMINIS: http://www.dartmouth.edu/~rmillan/ photogallery/minis.2005.sanae.html History

First hot air balloon – French brothers – 500ft. for about 5 miles in 1783 War time usage Many ‘Firsts’ – 1st to cross - 1785 – 1st to cross Atlantic – Double Eagle II - 1978 – and Pacific – Double Eagle V - 1981 – 1st non-stop around the world – Bertrand Piccard from Switzerland and Brian Jones from Great Britain in 1999

Military use of balloons: http://www.centennialofflight.gov/essay/Lighter_than_air/military_balloons_in_Europe/LTA4.htm Other Records • 2014 -- World's Highest Skydive! executive set a new mark Friday when he fell from an altitude of more than 135,000 feet, plummeting in a free- fall for about 5 minutes before deploying his . The jump broke the record of 127,852 feet that set in 2012 • Link http://www.npr.org/sections/thetwo-way/2014/10/25/358820835/-near-space-dive- sets-new-skydive-record-25-miles-above-earth • 2012 -- Felix Baumgartner, was highest skydive ever http://www.youtube.com/watch?v=6U6WDpWtbTY From 127,700 ft altitude • 1961 -- previous Altitude Record Set: Commander Malcolm Ross and Lieutenant Commander Victor A. Prather of the U.S. Navy ascend to 113,739.9 feet in 'Lee Lewis Memorial,' a polyethylene balloon. They land in the Gulf of Mexico where, with his pressure suit filling with water, and unable to stay afloat, Prather drowns. more• 2005 -- Hot Air High Altitude Record: On November 26, 2005, Vijaypat Singhania set the world altitude record for highest hot air balloon flight, reaching 21,290 m (69,850 ft). He launched from downtown Bombay, and landed 240 km (150 mi) south in Panchale

• 1995 -- First Solo Transpacific Balloon Flight: February 14- 17, Steve Fossett, another around-the-world contender with his Solo Challenger project, launches from Seoul, Korea and flies 4 long days to Mendham, Saskatchawan

• 2002 -- First Solo Round the World in a Hot Air Balloon: Steve Fosset, Started in Northam, Western Australia to , Australia. 13 days 12 hours 5 minutes (14 days 19 hours 50 minutes to landing), 20,482.26 statute miles (32,963 kilometers). This was Fossett’s 6th attempt at an around the world flight. • Want More? See http://www.pbs.org/wgbh/nova/balloon/science/history.html Priest missing on balloon flight April 2008 A Roman Catholic prest who used 1,000 helium balloons to try to break a flying record has gone missing off the southern coast of Brazil. Father Adelir de Carli lifted off from the port city of Paranagua on Sunday, equipped with a parachute, thermal suit, satellite phone and a GPS device. A sea and air rescue operation is under way after he lost contact with port authority officials late on Sunday. (happened in 2008) http://news.bbc.co.uk/1/hi/world/7360461.stm Or http://news.bbc.co.uk/2/hi/americas/7360416.stm Balloon types • zero pressure, super pressure, weather, blimp, tethered, cylinder, hot air, party

Tethered Aerostat He (blimp) NASA air bladder

semi-trailer Hot Air Balloons

• Montgolfier - rigid tissue paper over frame • Modern types are people numerous – nylon, etc • burners up to 15,000BTU or more ZeroPressure Balloons • Highest and lightest • Open at the bottom • no pressure difference across flanks

Sprite Balloon Test flight May 2002 Bob, Jeremy Michael Tillamook, OR Zero Pressure Balloon

When balloon gets to float altitude He has fully expanded and starts venting. Balloon stays at that Duct to vent Helium altitude no pressure difference across bottom and sides of balloon payload (only around the very top) Super Pressure Balloon • Longest Duration • Sealed Bag • Heavier (double layered – will not pop like rubber balloon) Spherical Superpressure balloon flights 1992/3

Launched from New Zealand

Record flights longest > 4 months

http://www.nsbf.nasa.gov/mission-txt.html Forces on a Balloon

• Gravity (on the balloon and the gas) • Pressure over the whole surface

Buoyancy – You get ‘lift’ if the weight of helium+balloon is less than the weight of the air displaced So, how much does air weigh? First lets talk about Density and pressure • Density is the technical term for how much mass is in a volume. • The more mass in a given volume, the higher the density • density  = m/V= mass/volume • Helium is less dense than air because each atom has less mass than molecules of Nitrogen (N2) and Oxygen (O2) Atmospheric Pressure

• Think about an ocean of air above us pressing down • Air pressure at sea level is 15 pounds/square inch. In other words, a column of air one inch square weighs about 15 pounds • A 1 square meter column of air weighs 39x39x15 pounds or nearly 23,000 pounds! Lift • Replace a volume of air with something that weighs less than that volume of air, BUT TAKES UP THE SAME VOLUME, and it will float • Density of He is much less than the density of air • Same number of atoms but each atom of He is lighter • Upward Force = Lift = L • Lift on the balloon is L= (weight of air displaced) – (weight of balloon+He+payload) My Experiments: Stratospheric Electrodynamics over Thunderstorms • Sprites and Lightning • Measure electric field, magnetic field, X- rays • Balloons in the stratosphere 10 to 15 hour flights with zero pressure balloons • Coordinated ground-based measurements/global location network Sprite scenario

balloon Pasko et al, 2006 stenbaek-nielsen, GRL, 2000