Course Layout AE-664: Lighter-Than-Air Systems

AE-664 Lighter-Than-Air Systems Chapter-00

Course Layout AE-664: Lighter-Than-Air Systems

Prof. Rajkumar S. Pant Aerospace Engineering Department

IIT Bombay

© Prof. Rajkumar S. Pant, All Rights Reserved


COURSE DESCRIPTION

P G Elective Course in Aerospace Engineering Institute Elective Course


1. Introduction & Historical Perspectives

2. Principles of Aerostatics

3. Airship Technology

4. Aerostat Technology

5. Remotely Controlled Airships & Tethered Aerostats

6. Current Developments & Future Trends

Six Capsules


Introduction to LTA Systems

Historical Developments

Key Subsystems and Components of LTA Systems

1: Introduction & Historical Perspectives


Variation of Atmospheric Properties

Static Lift Prediction

Effect of ambient conditions on Static Lift

Climb, Descent and Pressure Height

2: Principles of Aerostatics


Methodology for airship conceptual design

Aerodynamics & Stability analysis of Airships

Ground Handling and Mooring systems

Case Studies in Airship Operations

Design & Development of Remotely Controlled

Airships

3: Airship Technology


Methodology for sizing of Aerostat sub-systems

Equilibrium and Stability analysis of aerostats

Design and Development of Tethered Aerostats

4: Aerostat Technology


Challenges in design of LTA Systems

Hybrid LTA Systems

Stratospheric Airships

Current Trends and Recent Developments

6. Current and Future Developments


At the end of the course, you should be able to

Understand the differences between HTA and LTA systems

Estimate the static lift generated by an LTA system, given its type, size

and operating scenario

Carry out conceptual layout and sizing of an LTA system

Comment on the technological challenges in design, development and

operation of an LTA system

Comment on current developments and future trends of LTA systems

Anticipated Outcomes


In-Semester: 60%

Attendance 10%

Assignment s 20%

Moodle Participation: 10%

Quizzes: 20%

Examinations: 40%

Mid-Sem examination: 20%

End-Sem examination: 20%

Evaluation Scheme


Course Material on Moodle after class Most communication by e-mail from Moodle

No attendance to latecomers beyond 11:10 Unless they have a genuine reason !

Mobile Phones to be switched off (not mute) Or else I get to answer !

Audit requirements ≥ 80% attendance Submission of all Assignments

Questions and Interruptions most welcome !

Course Policies


Students with attendance < 50% : Zero marks Bonus marks for attendance > 50% ≥ 55% = 1 ≥ 60% = 2 ≥ 65% = 3 ≥ 70% = 4 ≥ 75% = 5 ≥ 80% = 6 ≥ 85% = 7 ≥ 90% = 8 ≥ 95% = 9 Missed none or only one class = 10

10 Marks for Attendance


[email protected]

Extn: 7127

208-F, First Floor, Aero. Engg. Deptt.

Last Room near CASDE backdoor

Meetings by prior appointments

Open Door policy for quick doubts

My Contact Details


Pant, R. S., Course Material for Design and Development of LTA systems,

Curriculum Development Program, IIT Bombay, 2010.

Taylor, J. A., Principles of Aerostatics, The Theory of Lighter-Than-Air

Aircraft, ISBN13:978-1-49481-053-5, 2014.

Khoury, G., Ed., Airship Technology, 2nd Edition, Cambridge Aerospace

Series, Cambridge University Press, ISBN 978-1107019706, 2012.

Carichner, G. E., and Nicolai, L. M., Fundamentals of Aircraft and Airship

Design, Volume 2 – Airship Design and Case Studies, AIAA Education

Series, ISBN: 978-1-60086-898-6, 2013, DOI: 10.2514/4.868986

Recommended Books


WHAT IS A LIGHTER-THAN-AIR SYSTEM ? Lets check out !


Introduction to Lighter-Than-Air Systems Prof. Rajkumar S. Pant

Aerospace Engineering Department IIT Bombay Spherical Aerostat


Aerostatic lift + Dynamic Lift

Highly fuel efficient

Less complex operating mechanisms

Slow

More susceptible to weather changes

Heavier than Air Systems

No Aerostatic Lift

Fuel inefficient

Complex mechanisms

Fast

Less susceptible to weather changes

Lighter Than Air Systems


Airship

• Lift: LTA Gas • Powered • Directional Control

Aerostat

• Lift: LTA Gas • Unpowered • Only stabilizing surfaces

Hot Air Balloon

• Lift: Hot Air • No Directional Control • Balloon Direction

depends on wind


Hot Air Balloon = simplest form of LTA System! Pix: Courtesy Wikipedia


Airships

Thrust

Lift

Weight

Drag

Enclosed volume of Helium provides the aerostatic lift without any use of additional energy

LB = V(ρa - ρg)


Components of an Airship

CONTROL SURFACES

ENVELOPE

GONDOLA


Types of Airships

Rigid

Non Rigid

Semi Rigid

Hot air


Hindenburg…Start of Hibernation @ Hindenburg

Largest airship ever built & launched in 1936 1,200-H.P. V-16 Mercedes-Benz Diesel engines 813 ft. long 16 bags of Hydrogen acquires 7,200,000 Cu. ft. ~ 10,000 miles, 5 - 6 days at cruise speed. Two 30-kW onboard diesel-powered generators Cruising across the Atlantic; 50- 60 hours Completed10.5 Germany-USA round trips

@ Disaster Lakehurst/New Jersey, 6th May 1937, 7 pm Dashed tower during landing ignited the gas 35 people died (22 crew, 13 pax)

o 62 people survived !


Revival by Skyship

Skyship 600


Modern Manned Airship


Ability to operate from open fields

Extremely high endurance capability

Stationary / low-speed flight allows on-board surveillance

systems to operate in high-clutter environment

Large cabin space and low vibrations reduces crew fatigue

Low noise, low environment pollution, unobtrusive vehicle

Varied applications as an aerial platform

USP of Airships


Advertisement & Product Promotion

Aerial Observation & Surveillance

Tourism and Corporate Hospitality

Landmine Counter Measures

Law Enforcement

Existing Applications of Airships


Advertisement & Product Promotion

http://www.airshipman.com/photogallery.htm


Aerial Observation


Tourism


Sports Tracking from A60+ operated by Metlife


Corporate Hospitality


MINESEEKER in KOSAVO

21/12/2006


Police Surveillance

1996 Olympics, Atlanta

2004 Olympics, Athens

Time Lapse Video Olympics 2012


Tethered Aerostat Systems


Aerostat: Introduction

Aerodynamically shaped tethered LTA platform

Payload: communication and surveillance equipment

Desired Features: Higher payload capacity Ability to maintain specified

altitude Stability in ambient wind

conditions Envelope shape affects all

these

Source: http://www.wsgi.com/

Wpay : 10 – 15 lb H : 700 – 2000 ft W : 500 – 750 lb L : 20 – 30 ft E : < 48 hours V : < 45 kt Ncrew

: 1


Envelope (He chamber) LTA Lifting gas

Air ballonet Pressure and Buoyancy control

Tail fins Static and Dynamic stability

Tether Attachment to the ground

Payload Radar, camera, transponders, ..

Ground station Winching Mooring

Parts of Aerostat


Moored Aerostat


Akashdeep Aerostat of DRDO, India


Why Aerostats ??


Aerostat Aircraft Needs good weather Can work in bad weather Remains Stationary Can achieve high speeds Zero fuel consumption Massive fuel Consumption Max. Endurance ~30 days Max. Endurance ~16 hours

Can be launched from any terrain

Requires specific terrain to be launched

Aerostat v/s Aircraft


Aerostats are highly cost effective

Aerostats are portable and can be re-located

Aerostats provide greater detail as they are closer

to the surveillance area

Aerostat v/s Satellite


Surveillance & Communication Border, Wide Area Land & Event Coverage Sea-Based Deployment, Military Intelligence Wireless, Long Range, High Speed, Last mile

Local aerial surveillance Aerodrome protection Balloon Barrage System Communications platform during emergencies Airborne Early Warning Radar System

Various Applications of aerostats


Joint Land Attack Cruise Missile Defense Elevated Netted Sensor system

Raytheon JLENS Aerostat


Used by meteorological department

Other Examples of aerostat

Source: British Meteorology Centre


World’s Largest Aerostat Used during Commonwealth Games 2010, New Delhi

40m X 80m X 12m

AE-664 Lighter-Than-Air Systems Chapter-01 3

www.ltascorp.com/bib.html


Oblate Spheroid with Sail

Picture: Courtesy ALTAVE, Sao Jose dos Campos, Brazil, www.altave.com.br


Rapid Elevated Aerostat Platform


Documents

Course Layout AE-664: Lighter-Than-Air Systems