1 april 26, 2007 balloon workshop on low cost access to near-space lcans:smith/swri l0w cost access...
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1April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
L0w Cost Access to Near Space
I. Steve Smith, Jr.
Southwest Research Institute
2April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
1783 : In the Beginning ( Montgolfier Brothers)
Balloon history started on 4 June 1783 with the ascent of the first hot air aerostat followed, on 27 August of the same year, by the launching of the first gas balloon (hydrogen).
3April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
Where Do They Fit in the Scheme of Where Do They Fit in the Scheme of Things?Things?
balloons
4April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
• Stratospheric balloons have…–Flown >8000 lb. payloads
–Flown large payloads to 160 k-ft.
–Flown >700 days duration
• Stratospheric balloons cannot…–Carry 8000 lb. To 160 k-ft for over 700 days
–Perform powered station-keeping
(Stratospheric balloons are not airships)
5April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
Balloon Altitude Stability Differences
Zero-Pressure Balloon (8% ballast mass/night or large altitude excursions)
Super-Pressure : No or minimal ballast requirement; Constant density float altitude
6April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
Types of Balloons
•Free Flyers–Gas
–Montgolfiers (Hot Air)
•Powered–Airships
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Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
Types of Gas Balloons
Zero-Pressure
Super - Pressure Hybrid
Stratospheric Airships
8April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
Zero–Pressure Balloons• “Open” system
• Maintains ~ 0 differential pressure at the base of the balloon
• Requires 8-10% ballast or dropping of mass each diurnal cycle to maintain altitude
• Erego…limited durations of 3-5 days in mid-latitudes except in polar regions
• Typical altitude excursion of 2-10 k-ft day to night
• Large payload capacity (see following chart)
• Sizes range from a few thousand ft3 to ~60 million cubic feet3 (mcf)
Most common balloon in use today
• RACOON is an unballasted version
• No ballast
• Altitude excursions ; 30-50 k-ft
• Durations dependant of atmospheric lapse rates or gas loss (20-60 days)
9April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
ZP Balloon Load Altitude CurvesSuspended Load vs. Altitude Capabilities
Based on 1962 Standard Atmosphere
90,000
100,000
110,000
120,000
130,000
140,000
150,000
160,000
170,000
0 1000 2000 3000 4000 5000 6000 7000 8000
Suspended Weight (lbs)
Geo
pote
ntia
l Alti
tude
(ft)
59.84 MCF
4.00 MCF 11.82-H MCF
11.82 MCF 29.47 MCF39.57-H MCF
39.57 MCF
ULDB - 21.56 MCF
*Balloon Volumes Noted in Million Cubic Feet (MCF)
10April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
Super-Pressure Balloons• “Closed” system---pressure vessel
• Maintains differential pressure within balloon
• Requires no ballast
• Requires high strength materials
• Durations weeks or months days anywhere globally (small SP flown fro several hundred days)
• Typical altitude excursions of 1-2 k-ft
• Payloads usually a few hundred pounds. ULDB/Pumpkin developing for 2000 lbs
• Sizes range from a few thousand ft3 to ~26 mcf
Spherical
Lobed: “Pumkin”
Tetroon
11April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
Types of Montgolfiers……Hot Air Balloons
• “Open” system
• Lift derived from heated gas
• Requires heat source to maintain altitude (propane, RTGs, etc)
• Some make use of thermal radiation sources (ie infrared or solar)
• Durations limited by availability of heat source
Montgolfier Infrarouge &
Solar Montgolfiers
Typical Hot Air
Solar Montgolfiers
12April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
Montgolfier Infra-Rouge
MIR vehicle (Montgolfiere Infra-Rouge) is a hot air balloon of 36000 to 45000 m3, with natural shape, only heated by radiative fluxes from the sun by daytime and upwelling infrared fluxes during the night.
13April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
Stratospheric Airships
Nov 2007
Nov 2005
2010
4/99 – 11/01 – 5/03
• Stratospheric Airships are powered, streamlined “balloons” designed to station-keep
• Relatively small payloads (10s-100s lbs)
• Altitudes usually 60,000 – 75,000 ft
• Durations : days to weeks
• Still under intensive development by DoD
• Only 2 have ever flown successfully under power (HiSentinel20); 20 lb sensor capacity
• Future is HAA of several thousand pounds
HiSentinel
14April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
HiSentinel Size Comparisons
Nov 2007
Nov 2005
2010
4/99 – 11/01 – 5/03
15April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
How Are They Launched?
By………..Land Sea Air
Dynamic DynamicStatic
16April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
Where are payloads mounted?
Middle
TopBottom
17April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
The Environment
18April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
Environmental : Variability
19April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
Environmental : Extreme
• Worse than orbiting spacecraft
• Very long eclipse times (12 hrs possibly)
• Very localized thermal IR extremes (thunder storms)
• Primary thermal driver is radiative (convection negligible)
• Atmosphere changes with time of year and latitude
• Tropopause temperatures are “generally” colder in summer and higher in altitude and are warmer and lower in winter
• Temperatures are “generally” warmer towards the poles
• Temperature of -90C can be seen
20April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
Environmental : Winds
Jaska 2005
Latitudinal Wind Profiles
• Winds vary with latitude, altitude and time of year
• NH winds blow westerly in the summer and easterly in the winter
• Turn-around occurs in spring and fall when stratospheric winds reverse.
21April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
How much can we see?
Stratospheric Fields of View Footprint Diameter to the Horizon
692 Miles520 Miles
80,000 feet
60,000 feet
847 Miles
120,000 feet
How much can we see?
22April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
What Can We See?
Prepared by O. Bruegman & G. Cashin/ITMI
Gamma Ray X Ray U V Optical I R
Alt
itu
de
(Fee
t x
1000
)
Atmospheric
Transmittence
Problems
Wavelength
Atmospheric Interference
& Water Vapor
Absorption of IR.
AtmosphericTransmittence
Problems
Olympus ENABLED SCIENCE
0
35
60
95
130
165
AtmosphericBackground
Interferes
130 k-ft
23April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
Imagination: Let it run wild
Venus
Titan
24April 26, 2007April 26, 2007
Balloon Workshop on Low Cost Access to Near-Space
LCANS:Smith/SwRI
Thank-You
I. Steve Smith, Jr.Southwest Research Institute