Ballonbau Worner NL-STU Technical specifications

Flight Manual
for GAS BALLOONS
of Type NL-STU
EASA.DE.21G. 0007
EASA.DE.M.F. 0560
EASA.DE.M.G. 0560
EASA.ADOA. 037
Ballonbau Wörner GmbH www.ballonbau.de
Zirbelstrasse 57c T: [phone]
86154 Augsburg F: [phone]
GERMANY E: [email protected]

Flight Manual for Gas Balloons of Type NL-STU
Flight Manual
for operation of gas balloons of type “NL-STU”
Issue 2.0 – Revision 2
May 10, 2019
Nationality
and registration markings _________________________________
Type _________________________________
Serial number _________________________________
Year of manufacture _________________________________
Manufacturer Ballonbau Wörner GmbH
Zirbelstrasse 57 c
86154 Augsburg
Germany
The balloon specified above is to be operated in accordance with the procedures described
herein and the prescribed operating limits. The information contained in the Flight Manual must
be available in the basket during flight.
This Flight Manual is certified by the EASA.
EASA Certification number: 10058411
Date of Certification June 13, 2016
The latest revised issue of this Flight Manual is published on the Internet page
www.ballonbau.de.

Flight Manual for Gas Balloons of Type NL-STU
Issue 2.0 May 02, 2016 Page I
0.0 Weighing report
PRELIMINARY OBSERVATION: For reasons of legibility, male pronouns are used through-
out this Flight Manual. All details referring to persons apply equally, however, to both men and
women.
kg
Date of
weighing Performed by
Maximum mass acc. to data sheet
Empty mass at unit testing
Reweighings

Flight Manual for Gas Balloons of Type NL-STU
Issue 2.0 May 10, 2019 Page II
0.1 Revision history
Any changes to this Flight Manual, with the exception of a new weighing, must be recorded in
the following table. The date of the revision is indicated at the bottom of the revised page.
All modifications made to the Flight Manual prior to approval of Issue 2.0 of this Flight Manual
have been incorporated into this version.
Rev.
no.
Subject / Affected
sections
Affected
pages
Date of
Issue
EASA
Approval no./ Date
1
Light weight basket with fabric
wall
0.1 Revision history II 25.07.2016 10059371/12.09.2016
0.2 List of effective pages IV 25.07.2016 10059371/12.09.2016
Contents V - VIII 25.07.2016 10059371/12.09.2016
2.5 Approved envelop/basket
combinations 2-4 25.07.2016 10059371/12.09.2016
2.7.2 Basket size and number of
occupants 2-5 25.07.2016 10059371/12.09.2016
4.4.2.2 Toggle fastening to the load
ring 4-3 25.07.2016 10059371/12.09.2016
4.4.2.3 Ballast bags 4-5 25.07.2016 10059371/12.09.2016
4.11 Landing 4-15 25.07.2016 10059371/12.09.2016
5.3.2 Basket 5-2 25.07.2016 10059371/12.09.2016
5.3.3 Matrix of theoretically possi-
ble loads 5-3 25.07.2016 10059371/12.09.2016
6.4 Basket 6-2 25.07.2016 10059371/12.09.2016
8.2 Checklists 8-2 25.07.2016 10059371/12.09.2016
2
0.1 Revision history II 10.05.2019 10069974/22.05.2019
0.2 List of effective pages IV 10.05.2019 10069974/22.05.2019
Contents VIII 10.05.2019 10069974/22.05.2019
1.0 General warning 1-1 10.05.2019 10069974/22.05.2019
1.7 Labeling of the components 1-5 10.05.2019 10069974/22.05.2019
2.3 Condition of the balloon 2-3 10.05.2019 10069974/22.05.2019
2.12 Further constrains 2-7 10.05.2019 10069974/22.05.2019
4.5 Inflating with lifting gas 4-8 10.05.2019 10069974/22.05.2019
4.10.4 Dropping ballast 4-14 10.05.2019 10069974/22.05.2019
8.2 Checklists 8-2 10.05.2019 10069974/22.05.2019
Appendix A-1 10.05.2019 10069974/22.05.2019

Flight Manual for Gas Balloons of Type NL-STU
Issue 2.0 May 10, 2019 Page III

Flight Manual for Gas Balloons of Type NL-STU
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0.2 List of effective pages
NOTE: The sections or pages specially marked with the abbreviation “appr.” have been approved by
EASA.
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Appendix 1
Appendix 2
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Flight Manual for Gas Balloons of Type NL-STU
Issue 2.0 July 25, 2016 Page V
Contents Page
0.0 Weighing report....................................................................................................I
0.1 Revision history...................................................................................................II
0.2 List of effective pages ....................................................................................... IV
Chapter 1 – General information
1.0 General warning ............................................................................................1-1
1.1 Introduction ....................................................................................................1-1
1.2 Certification basis ..........................................................................................1-1
1.3 Definitions and list of abbreviations ................................................................1-2
1.4 Warning, Caution and Note ............................................................................1-3
1.5 General description ........................................................................................1-3
1.6 Description of a gas balloon ............................................................................1-4
1.7 Labeling of the components ...........................................................................1-5
Chapter 2 – Operating limits
2.1 Introduction ....................................................................................................2-1
2.2 Weather conditions ........................................................................................2-1
2.3 Condition of the balloon .................................................................................2-2
2.4 Lifting gas ......................................................................................................2-3
2.5 Approved envelope/basket combinations .......................................................2-4
2.6 Minimum ballast .............................................................................................2-4
2.7 Number of persons in the basket ...................................................................2-5
2.7.1 Minimum crew ..............................................................................2-5
2.7.2 Basket size and number of occupants .............................................2-5
2.8 Minimum equipment ......................................................................................2-5
2.9 Appendix ........................................................................................................2-6
2.10 Maximum rate of climb and descent ...............................................................2-6
2.11 Operating the parachute as a maneuvering valve ............................................2-6
2.12 Further constraints .........................................................................................2-7
Chapter 3 – Emergency procedures
3.1 Introduction ....................................................................................................3-1
3.2 Behavior in the event of gas fires ...................................................................3-2
3.3 Closed appendix during take-off and ascent ..................................................3-3
3.4 Overcoming obstacles at low altitude .............................................................3-3
3.5 Contact with overhead power lines ...................................................................3-4
3.6 Damage to the envelope in the air .................................................................3-5
3.7 Excessive pulling of the parachute .................................................................3-5
3.8 Malfunction and defect of the parachute ........................................................3-6
3.8.1 Defect of the parachute and parachute line ..................................3-6
3.8.2 Conspicuously low pulling force required to open the parachute .....3-6

Flight Manual for Gas Balloons of Type NL-STU
Issue 2.0 July 25, 2016 Page VI
Page
3.9 Sudden loss of lifting gas ...............................................................................3-7
3.10 Non-standard landings ...................................................................................3-7
3.10.1 Hard landing .................................................................................3-7
3.10.2 Landing in woodland .....................................................................3-8
3.10.3 Landing on water ..........................................................................3-9
Chapter 4 – Standard operating procedures
4.1 Introduction ....................................................................................................4-1
4.2 Weather ........................................................................................................4-1
4.3 Preflight checks .......................................................................................4-1
4.4 Preparing for inflation .....................................................................................4-2
4.4.1 Take-off site ..................................................................................4-2
4.4.2 Preparing the balloon up to the start of inflation ............................4-2
4.4.2.1 Laying out the envelope ..................................................4-3
4.4.2.2 Toggle-fastening the load ring .........................................4-3
4.4.2.3 Ballast bags ....................................................................4-5
4.4.2.4 Preparing the envelope ...................................................4-5
4.4.2.5 Inflation method for envelope held down with sand bags 4-6
4.4.3 Attaching the inflation tube ...........................................................4-7
4.5 Inflating with lifting gas ...................................................................................4-8
4.6 Making the ropes ready ...............................................................................4-10
4.7 Flight ballast ................................................................................................4-11
4.8 Preparing for take-off .....................................................................................4-12
4.8.1 Checking the weather situation ...................................................4-12
4.8.2 Checking the equipment .............................................................4-12
4.8.3 Instructing the passengers ..........................................................4-12
4.8.4 Opening the appendix ................................................................4-13
4.8.5 Trial pull of the parachute ...........................................................4-13
4.9 Take-off ......................................................................................................4-13
4.10 Flight ......................................................................................................4-13
4.10.1 Checking the ropes ....................................................................4-14
4.10.2 Venting the lifting gas .................................................................4-14
4.10.3 Observing the variometer ...........................................................4-14
4.10.4 Dropping ballast .........................................................................4-14
4.11 Landing ......................................................................................................4-15
4.11.1 Orienting the basket ...................................................................4-16
4.11.2 Touch-down ...............................................................................4-16
4.12 Deflating the envelope .................................................................................4-17
4.13 Dismantling and packing ..............................................................................4-17
4.14 Packing tarp .................................................................................................4-19

Flight Manual for Gas Balloons of Type NL-STU
Issue 2.0 July 25, 2016 Page VII
Page
Chapter 5 – Size and weights
5.1 Introduction ....................................................................................................5-1
5.2 Sizes ........................................................................................................5-1
5.3 Standard sizes and maximum dimensions .....................................................5-2
5.3.1 Envelope ......................................................................................5-2
5.3.2 Baskets .......................................................................................5-2
5.3.3 Matrix of theoretically possible loads ........................................ 5-3
Chapter 6 – Components of the gas balloon
6.1 Introduction.......................................................................................................6-1
6.2 Envelope ........................................................................................................6-1
6.2.1 Material .......................................................................................6-1
6.2.2 Openings in the envelope .............................................................6-1
6.2.2.1 Deflation opening ............................................................6-1
6.2.2.2 Emergency opening ........................................................6-1
6.2.2.3 Appendix opening..............................................................6-2
6.2.3 Load belt .....................................................................................6-2
6.3 Load ring ........................................................................................................6-2
6.4 Basket .......................................................................................6-2
6.5 Sand bags and sand containers .....................................................................6-3
6.6 Trail rope .......................................................................................6-3
6.7 Ropes .......................................................................................6-3
6.7.1 Holding ropes ...............................................................................6-3
6.7.2 Parachute line ..............................................................................6-3
6.7.3 Emergency opening line ...............................................................6-3
6.7.4 Appendix pull-close line ................................................................6-4
6.7.5 Appendix anchor line ....................................................................6-4
6.8 Electrostatic charging .....................................................................................6-4
6.9 Inflation aid ....................................................................................................6-4
6.10 Instruments ....................................................................................................6-5
6.10.1 Altimeter..........................................................................................6-5
6.10.2 Variometer.......................................................................................6-5
Chapter 7 – Servicing, maintenance and inspection
7.1 Introduction ....................................................................................................7-1
7.2 Inspection intervals .......................................................................................7-1
7.3 Preventive maintenance ................................................................................7-1
7.4 Transport by road .......................................................................................7-2
7.5 Cleaning and upkeep .....................................................................................7-2
7.6 Storage .......................................................................................7-3

Flight Manual for Gas Balloons of Type NL-STU
Issue 2.0 May 10, 2019 Page VIII
Page
Chapter 8 – Checklists
8.1 Introduction ....................................................................................................8-1
8.2 Checklists .....................................................................................................8-1
Chapter 9 – Combination with components from other manufacturers
9.1 Introduction ....................................................................................................9-1
9.2 Basket ........................................................................................................9-1
Appendix 1 – Ultramagic TEKNO Basket …………………………………………..................A1-1
Appendix 2 – Use of the fabric walled basket …………………………..………...................A2-1
Appendix 3 – Handling of gases during operation of balloon type NL-STU ..................A3-1

Flight Manual for Gas Balloons of Type NL-STU
Issue 2.0 May 10, 2019 Page 1-1
Chapter 1 – General information
1.0 General warning
The gas balloon is an aircraft. It thus brings with it all the risks and inherent dangers associated
with the aircraft type and of aviation in general.
Ballooning can be dangerous!
It is the responsibility of the owner/operator to ensure that the balloon is operated in an airwor-
thy condition. For this reason, maintenance work, repairs and inspections must be performed
conscientiously in order to prevent personal injury to persons and damage to property.
The pilot must be licensed in accordance with the applicable aviation regulations and keep in
practice.
Care is required, when handling the lifting gas. There is a danger of, among others, ignition of
mixtures of gas, a danger of suffocation as well as a danger of burst of the envelope.
There is a risk of fatal injury!
1.1 Introduction
This Flight Manual is intended to provide pilots and instructors with the information and assis-
tance required to enable the safe operation of gas balloons of type “NL-STU” from Ballonbau
Wörner.
The latest version of the Flight Manual can be found on the Internet page www.ballonbau.de.
Instructions for Continued Airworthiness and any technical modifications will be published by
means of Service Bulletins and/or Technical Notes and displayed on the Internet page.
In addition to the instructions contained in this Flight Manual, the pilot must also comply with the
applicable national regulations. This applies to the regulations in both the country over which he
is flying and the country in which the balloon is registered.
1.2 Certification basis
The certification basis are the “Preliminary Requirements for Manned Gas Balloons” (LBA file
number I1-602.4/50/4/91).
The gas balloon “Wörner NL-STU” is certified by EASA with the Type Certificate No.
EASA.BA.009 and by the FAA with the Type Certificate No. B03CE.

Flight Manual for Gas Balloons of Type NL-STU
Issue 2.0 May 02, 2016 Page 1-2
1.3 Definitions and list of abbreviations
Wind speed at ground level The mean wind speed measured 2 meters above the
ground.
EASA European Aviation Safety Agency
Units:
Meters - feet: 1 m = 3.28084 ft 1 ft = 0.3048 m
Cubic meters - cubic feet 1 m³ = 35.3147 ft³ 1 ft³ = 0.0283 m³
Kilometers per hour - knots: 10 km/h = 5.5 kt 10 kt = 18 km/h
m/s - ft/min: 1 m/s = approx. 200 ft/min 100 ft/min = approx. 0.5 m/s
Kilograms - pounds: 1 kg = 2.204 lb 1 lb = 0.454 kg
FAA Federal Aviation Administration
FAI Fédération Aéronautique Internationale
ISA standard atmosphere
Standard air pressure: 1013.25 hPa
Standard air temperature: 15 °C
Standard air density: 1.225 kg/m³
Persons in basket Pilot and passengers
Service Bulletins Maintenance notifications
VFR
Visual flight rules; set of regulations under which a pilot op-
erates an aircraft in weather conditions generally clear
enough to allow the pilot to see where the aircraft is going.
Maintenance manual
Refers here to the manual “Instructions for Continued Air-
worthiness” from Ballonbau Wörner. This maintenance
manual is applicable to “NL-STU” gas balloons.

Flight Manual for Gas Balloons of Type NL-STU
Issue 2.0 May 02, 2016 Page 1-3
1.4 Warning, Caution and Note
WARNING: Failure to observe the procedures described will result in direct or serious
deterioration of flight safety.
CAUTION: Failure to observe the procedures described will result in minor or more-or-less
long-term deterioration of flight safety.
NOTE: Highlights a specific point that does not directly affect safety, but is important or
unusual.
1.5 General description
A manned gas balloon is a “lighter-than-air” aircraft. It consists of a gas-tight envelope with a
basket suspended beneath it. The basket is attached to the envelope by means of ropes. The
lifting gas is generally hydrogen or helium. The balloon rises by dropping fine sand ballast,
thereby making the balloon lighter. During flight, descent of the balloon can be initiated by vent-
ing lifting gas from the envelope. The balloon can only be steered by changing altitude, as
winds generally blow in different directions at different altitudes.

Flight Manual for Gas Balloons of Type NL-STU
Issue 2.0 May 02, 2016 Page 1-4
1.6 Description of a gas balloon
A complete description of the gas balloon and its layout can be found in Chapter 6 of this Flight
Manual.
Fig. 1: Schematic representation of a gas balloon of type NL-STU

Flight Manual for Gas Balloons of Type NL-STU
Issue 2.0 May 10, 2019 Page 1-5
1.7 Labeling of the parts
The manufacturer, type, registration number, serial number and year of manufacture are indi-
cated on the identification plate. The identification plate is attached in the following positions:
Fig.2:
Marking on the envelope: stain-
less steel plate on the clamping
ring of the appendix
Fig.3:
Marking on the load ring:
flexible plate
Fig.4:
Marking on the basket:
brass plate in the basket.

Flight Manual for Gas Balloons of Type NL-STU
Issue 2.0 May 02, 2016 Page 2-1
Chapter 2 – Operating limits
2.1 Introduction
This section defines the operating limits for flying the gas balloon and for its standard equip-
ment.
2.2 Weather conditions
Assessment of wind and weather forecasts is of the utmost importance for safe ballooning.
2.2.2 Maximum wind speed
During inflation, the average wind speed should not exceed 12 knots with gusts not exceeding
a maximum of 15 knots.
For take-off, the wind speed should not exceed 15 knots.
CAUTION: At the maximum wind speeds, inflation can only be carried out by an experienced
inflation team!
NOTE: The maximum wind speed at ground level for a safe take-off depends on the
specific conditions at the take-off site and on the ability of the pilot.
2.2.3 Thermals and gusts
If strong thermals are forecast, the balloon should be landed as soon as the thermals arise, if
possible, or the flight should be planned in such a way that the flight altitude is high above the
thermals and the balloon is landed at the end of the thermals.
2.2.4 Thunderstorms and severe weather
The balloon must not be flown in thunderstorms or other severe weather conditions of any kind.
WARNING: If meteorological conditions are thundery, there is a risk of dangerous turbulence
and strong wind shear. There is a major risk of electrostatic discharge. It is also
possible that the balloon might be pulled up to high altitudes with little oxygen
and low temperatures.
2.2.5 Night flights
The flight must be planned to enable landing in daylight.
CAUTION: Landing at night is dangerous, as possible obstacles, such as overhead power
lines, cannot be seen.

Flight Manual for Gas Balloons of Type NL-STU
Issue 2.0 May 02, 2016 Page 2-2
2.2.6 Flights at temperatures below freezing
When the envelope is stored in the packing sack, creases are formed. At temperatures above
0 C, these creases are smoothed by the tension of the envelope. At temperatures below 0 C,
the tension of the envelope may be insufficient to smooth the creases around the parachute
opening. Under certain circumstances, this could result in gas leaks, because the parachute will
not close properly.
Measures for reducing crease formation:
• Attach the edge protection of the parachute opening after landing
• Remove upper area of envelope from the packaging for approx. two hours before infla-
tion, lay it out in a circle and allow to warm up to around 20 C indoors. This enables the
folds to smooth out.
Measures for ensuring gas-tightness:
• Do not subject the parachute opening to loading in the kinked state in order to prevent
creasing when cold.
• Stop inflation when the inflation level corresponds to a full envelope at the expected
maximum flight altitude and listen out that there is no sound of gas escaping.
• If you intend to take off with the envelope not taut, perform the trial opening of the valve
by pulling the line after the desired inflation level has been reached.
• If you intend to take off with the envelope taut, continue to inflate until the maximum level
and leave the parachute opening subjected to the maximum possible envelope tension
for as long as possible before take-off. Perform the trial opening of the valve.
• In the case of inflation at night, it may be necessary to delay take-off until the edge of the
parachute opening has warmed up and turned smooth during the day. This can be
detected by means of a visual inspection or possibly seen as the envelope becomes taut
while the appendix is closed.
CAUTION: If inflation and flight are to be carried out at temperatures consistently below 0°C,
the ballast quantity and the anticipated flight path must be planned to enable the
balloon to land with a slight gas leak.
2.3 Condition of the balloon
WARNING: If damage impairing airworthiness is detected during the preflight checks, take-off
is not permissible!
NOTE: All damage resulting in loss of airworthiness of the balloon must be repaired in
accordance with the maintenance manual.

Flight Manual for Gas Balloons of Type NL-STU
Issue 2.0 May 10, 2019 Page 2-3
Damage resulting in loss of airworthiness:
• Tears at the parachute opening
• Damage to the parachute and its belts
• Holes or tears in the envelope that are larger or longer than 5 mm
• Detached envelope reinforcements at the north pole and at the load belt
• Damaged seams at the load belt
• Broken or deformed stainless steel rings at the load belt
• Damaged parachute line
• Damaged suspension ropes with less than 70 percent of the cross section intact
• Damaged load ring slings with less than 70 percent of the cross section intact
• Deformed load ring
• Damaged basket ropes
• Defective emergency opening line
NOTE: The permissible limits for damage are described in Chapter 2 of the maintenance
manual.
NOTE: A condition that may limit airworthiness is: moisture inside the envelope.
CAUTION: Temperatures below 0 degrees Celsius may result in the parachute freezing to
the envelope. An envelope that is moist inside may only be filled if it can be as-
sured that:
•the parachute itself and an area 1 meter wide around the parachute opening are
dry or
•have first been rubbed dry with a cloth.
2.4 Lifting gas
Gases that may be used for filling the envelope are hydrogen, helium and coal gas (city gas).
The correct handling of the lifting gas is described in Appendix 3.
NOTE: Coal gas has a lower lifting capacity than hydrogen or helium. The pilot should be
aware of the different response characteristics of the balloon in this case.
NOTE: Hydrogen is a tasteless, odorless and colorless combustible gas. Escaping hydrogen
gas can displace breathable air, resulting in a risk of asphyxiation! Burning off of a
hydrogen/oxygen mixture can change suddenly into a detonation with generation of
pressure and heat. The particular hazards resulting from these properties must be
taken into consideration in a training course dealing with the handling of hydrogen. All
participants must be instructed in the hazards and safety measures applicable when
working with hydrogen and relevant to the local situation.

Flight Manual for Gas Balloons of Type NL-STU
Issue 2.0 July 25, 2016 Page 2-4
NOTE: Helium is a very light, non-combustible, non-toxic, colorless and odorless gas. Inhala-
tion of helium can lead to unconsciousness, respiratory arrest and in the worst case
death. This may occur without any prior indications or symptom.
2.5 Approved envelope/basket combinations
Envelope 280 m³ 380 m³ 510 m³ 640 m³ 840 m³ 1000 m³
Basket I
80 x 65 cm x
Basket II
95 x 80 cm xxx
Basket III
110 x 95 cm xxx
Basket IV
125 x 105 cm xxxxx
Basket V
135 x 115 cm x x x x
Basket VI
145 x 125 cm x x x
Lightweight basket
125 x 105 cm xxxxx
Fabric walled basket
125 x 105 cm xxxxx
x = permissible combination
2.6 Minimum ballast
Loading may only be carried out in compliance with the prescribed minimum ballast quantity. If
necessary, the number of passengers must be reduced for flights in order to ensure that the
actual quantity of ballast does not fall below the specified minimum ballast quantity. The pre-
scribed minimum ballast quantity is as follows:
Balloon size 280 m³ 380 m³ 510 m³ 640 m³ 840 m³ 1000m³
Sand bags of
15 kg each 2 3 3 4 4 5
NOTE: The minimum ballast is reserved only for landing operations. Additional flight
ballast is used for flight operations.

Flight Manual for Gas Balloons of Type NL-STU
Issue 2.0 July 25, 2016 Page 2-5
2.7 Number of persons in the basket
The maximum number of persons in the basket is determined first by the minimum ballast and
secondly by the size of the basket. An area of min. 0.3 m² must be available for each person.
2.7.1 Minimum crew
The minimum permissible crew is 1 pilot.
2.7.2 Basket size and number of occupants
Envelope 280 m³ 380 m³ 510 m³ 640 m³ 840 m³ 1000 m³
Basket I
80 x 65 cm 1 person
Basket II
95 x 80 cm 2 persons 2 persons 2 persons
Basket III
110 x 95 cm 3 persons 3 persons 3 persons
Basket IV
125 x 105 cm 4 persons 4 persons 4 persons 4 persons 4 persons
Basket V
135 x 115 cm 5 persons 5 persons 5 persons 5 persons
Basket VI
145 x 125 cm 6 persons 6 persons 6 persons
Lightweight basket
125 x 105 cm 4 persons 4 persons 4 persons 4 persons 4 persons
Fabric walled basket
125 x 105 cm 2 persons 2 persons 2 persons 2 persons 2 persons
Maximum permissible number of occupants
2.8 Minimum equipment
For flights under visual flight rules, the following minimum equipment must be on board:
1 variometer
1 altimeter
1 hook knife
1 first aid kit