Balloon Life,
December 2000
A boomerang travels away from the
thrower, and then turns 180 degrees and
returns. Certain wind conditions can cause
a balloon to make a similar journey. How
often has the wind switched on you? On
the ground? In the air? During inflation?
During deflation? When you least ex-
pected it? There are only a few causes for
wind switches, and balloonists must be
prepared to deal with these at any time.
Background
Majorfrontalactivity(cold,warm,
stationary), as well as micrometeorologi-
cal disturbances can causewinds to change
directions and velocities.To review,cooler
air isheavier thanwarmairbecause the
various molecules in air (carbon dioxide,
oxygen,nitrogen,watervapor,etc.) are
closertogether(denser).Allothervari-
ables being equal, cooler air sinks, while
warmer air rises.Windsthatchange di-
rection or velocity due to heating or cool-
ing of the ground (or trees, water, asphalt,
etc.) in flat areas or in valleys and hills,are
familiartoallballoonists.Inthecool
nightandmorning, the cooler mountain/
hill air flows downthe mountain/hill and
down the valley. As the radiant heat ofthe
sunheats the ground, the windswitches,
risingbyconvectionbackupthe valley
andmountain/hill.Theseareknownas
katabatic(down;drainage)andanabatic
(rising; uphill) winds,respectively.In and
aroundAlbuquerque,forexample,this
switchcanoccurduringinflationina
matter of 30-60 seconds, and insteadof a
fourknotwindaidingyour inflator and
burner, youwatch the envelope top cav-
ing backwards towards you. Quick action
usually averts the burned nylon syndrome.
TheAlbuquerque“box”issuchaphe-
nomenon,compoundedbytemperature
inversions, which allow the winds to travel
indifferentdirectionsatdifferentalti-
tudes, oftena 180 degree difference.
Cyclonicwindsareproducedbya
complicated set of meteorological condi-
tionsprecededbyalowpressurearea,
oftensmallinthe beginning. They rotate
counterclockwiseinthenorthernhemi-
sphere. Thermalsareexamplesofsmall
lows produced by radiant sun energy con-
vertedtoconventionheatingandrising
warmerair,withsurroundingairfrom
above andsides rushing intofill the low
createdbythe upliftingair. Rotationbe-
ginsgentlyatfirst,andifyourballoon
enters such a beginning “willy-willy,” as
youflythroughtherotatingwind,you
change direction. If you’re lucky enough
to fly through all or part of this micro-low
and out the other side before the rising air
inthecentercarriesyouup,youwill
changedirectionanywherefroma small
amountto360degreesormore.Once
you’renolongerinthemicro-cyclone,
youwillgenerallyresumeyouroriginal
direction.
Eddy currents also produce low pres-
sure areas, andcan be createdby a linear
airmassblowingoverrelativelysolid
obstructionsofanykind,suchashills,
buildings, silos, solid towers, large trees,
etc. These eddies alsocause air direction
and velocity disturbance, and can create a
wind directionswitch. Large-scalefron-
tal activity can add variety to any of these
micro-environments.
The results of one kind of wind switch,
thisone after landing, came tomyatten-
tion a few years ago. I thought it was rare
untilIbeganinvestigating,anddiscov-
ered seven probable instances in the Rocky
Mountainarea aloneinwhichaballoon
had landed, and then gone backwards into
apowerline.Manypilotsreportwind
switches after landing in which no power-
lines or fences or buildings or towers are
present, and therefore no damage occurs,
and the tailgate debriefing is simply inter-
esting rather than harrowing. I believe
this effect is an often overlooked problem
in landings, and much more common than
reported. The phenomenon reminds me
of the path of a boomerang.
Incident
This incident occurred in Rapid City,
SouthDakotaSeptember4,1993.The
balloon was an Aerostar S55-Amarried to
a Rally I wicker basket, with a single HP-
2 burnerand three 10 gallon Worthington-
type aluminum propane tanks with appro-
priatemanifold.Theusualinstrumenta-
tionincludedagalvanometer-typetem-
peraturegauge(pyrometer)utilizinga
thermocouplesewnontheinsideatthe
envelope crown-body junction, with wire
leading down the inside of the envelope to
the gondola. The envelope had been retro-
fitted with a springtopandparavent.
Thepilotwasa57-yearoldwhite
malewith70hoursofballoontimein
type, over two year’s duration. His occu-
pation was fixed-wingpilotfor a meteo-
rological research team, with about 12,000
hourstotalflyingtime, (10,500infixed
wing aircraft of manytypes,about1500
hoursinrotor-craft)includingtwoViet-
namtours, with800combatmissionsin
F-4s.Heholdssingle-andmulti-engine
land and seaplane, rotorcraft, gyrocopter,
instrument, flight instructor, air transport,
and other certificates and ratings. He has
neverhadanFAAviolation(andstill
doesn’t), nor a moving-vehicle violation.
Thepassengerwasa35yearold
whitemale,whooftencrewedforthe
pilot, and had had several balloon rides in
the past.
All preflight preparations were stan-
The Boomerang Effect:
After Landing
by Thomas S. McConnell, MD
Balloon Life,December 2000
dard and nominal, including two FAA
Flight Service Station weather briefings
(onethe nightbefore, one the morning of,
the flight).Weather at inflation was bro-
ken clouds, ground winds NNE at four
knots, SW at 12 knots at 1000 feet AGL,
SW at 14 knots at 2000 feet AGL and
WSW at 10 knots at 3000 feet. Visibility
10 miles, clear sky, no haze. Temperature
54 degrees at dawn and 65 degrees at 9:30
a.m., the approximate time of the incident.
One other balloon inflated alongside
this pilot, in Sioux Park, common to bal-
loon inflations. This pilot had launched
about 20 times from this spot. Inflation
and ascension were nominal. The balloon
Cowboy (“M”)
Hill
Hangman
Hill
Graphic notto scale
Balloon Life,December 2000
The pilot then began thinking about land-
ing,and began looking for a promising site.
His estimated ground speed was less than
ten knots. He made a gradual descent to
about200feetAGLthroughanareaknown
asThe Gap (where two hillscome together
as Rapid Creek runs through the lowest
spot), when he spotted a city park (Flood
PlainPark, between Mountain View Road
and Canal Street) just south of M Hill (in
which he had landed once before, and in
which he knew other balloons had landed),
with RapidCreek, a jogging path and some
115 KV powerlines to his right (NW)and
4-lane Omaha Street to his left(SE).About
50% of his fuel had been expended by this
time, about 70 minutes into the flight.
He descended fairly slowly, because
he estimated about 200 yards between the
street, which had no powerlines or other
obstructionsadjacentto the intended point
of landing, and the powerlines (there were
lightpoles)adjacent to the intended point
of landing, and the powerlines next to the
creek [thisestimatelater proved tobe a 363
foot overestimate], which he estimated to
be about 60 feet high. This distance ex-
panded towardthe SW (thedirectionof his
flight), but narrowed back toward the NE
(thedirectionfrom whichhe was coming).
Hedescend carefully,slowing to about
five knots,readyinghispassenger for land-
ing, and then once over the powerlines,
clearingthem byatleast100feet,hestopped
burning, made a standup landing without
crew, using the vent portionof the top, and
after a drag of perhapstenfeet, the balloon
came to a stop. About ten seconds after
comingto a stop, the balloonbegan slowly
dragging back in a NNE direction. While
the pilot began ripping out, a fellow bal-
loonpilotcamerunningupandgrabbedthe
basket. The balloonpicked up speed (esti-
mated at eight knots), the pilot pulled the
red linewithrenewed vigor, ashard andfar
as possible, hollered to “Standclear of the
balloon” (twice), threwhis leg over the
side of the basket and began helping his
passenger to exit the basket. The balloon
rotated somewhat, a loud“zap” was heard,
both pilot and passenger were now out of
the balloon, and within seconds, the enve-
lope deflated back towards the SSW (the
originaldirectionoftraveljustbefore land-
ing), the spring top being then wide open.
About 25-30secondshadelapsed from
touchdown to deflation.
Pilot andpassengerlooked around,
and saw the fellow balloonistlying on the
ground, “on fire.” The pilot rolled the fel-
lowover to extinguishthe fire, saw he was
not breathing, felt for a neck pulse, and
finding none, began cardiopulmonary re-
suscitation. About the time the fellow
coughed and had a neck pulse, a fireman,
coincidentallyjoggingthat morningonthe
footpath nextto thecreek, arrived onscene
andtook over resuscitation. Anambulance
arrivedsoonafter, andthe fellowwastrans-
ported to the hospital, where electrical en-
try burns were seen on his right hand and
right shoulder, and an exitburn on his left
foot. A slow recovery from burns ensued.
The FAA investigator termed the happen-
ing an “incident,” and damage to the bal-
loon consisted of burn holes in the enve-
lope in the vicinity of the pyrometer wire,
and to the instruments and metal support-
ing structures (uprights).No monetary es-
timate was given. Later measurements re-
vealed, from pointoftouchdowntopower-
lines, 179feet, andto theedge of the street,
58 feet. Remember that the radius of an S-
55 at the equator is 27.5 feet, so that the
distance of travel of the basket to power-
line contact was about 151 feet.
Analysis
Among many, these questions must
be considered: 1) What caused the wind
switch? 2) Did the pilot land too close to
thelines, or indeeddidhe chooseanappro-
priate landing site? 3) After landing, and
the wind switch, did the pilot perform all
the correctprocedures, or were there some
things he should not have done, or have
done differently? 4) Was the pilot appro-
priately trained and experienced, and did
he useappropriate judgement (in safety
seminars, we call it “pilot decision mak-
ing”)? 5) Didthefellowballoonist (an
experienced, 300+hour commercial rated
hot-air balloonist, who we know attended
at least one safety seminar attended by the
pilot in command of this story, and his
instructor, both of Rapid City)behave ra-
tionally, according to his training, experi-
ence and common sense?
1) Themost probable causeof this
approximately130 degree windswitchaf-
ter landingwas the combination of frontal
activityaloft;landingontheleeward(down-
wind) side of a hill; two hills coming to-
getherwitha creekbetween 500yards
upwind of the landing site, forming a po-
tential funnel effect; and possible thermal
activity caused by convective heating of
the ground, in between cooler areas adja-
cent, such as the creek. However, I am less
interested in what caused the wind switch,
than a pilot knowing of the possibility.
2)Some teach not to land closer than
300 feet from powerlines, and some, 500
feet, upwind or downwind. However, in
every seminar and in all student pilot in-
struction, we also teach that “pilotin com-
mand” has a certain meaning, and that all
circumstances must be evaluated,in the
context of thatparticular flight, and allthe
aspectsof it, and that the pilotincommand
makes the final decision. I have not landed
a balloon at this site, but I have seen it,
walked over it, measured it. I might have
landed there under certain circumstances,
and I would not have landed there under
other circumstances. Three hundredfeet is
the length of the playing portionof a foot-
ball field; this balloon came down on the
60 yard line from the powerlines. Many
would say this is too close. This pilotnow
says he does not land that close to power-
linesany more. Thisincidenttooklessthan
a minute to play itself out. My plea is that
we thinkconservativelyaboutthepossibil-
ityof moving back toward the powerlines,
or some other obstruction, every time we
land. Thinking about this boomerang ef-
fect must precede landing.
3) There are two schools of thought
about where pilot and passengers should
be in a powerline contact: a) get out (get
everyone out) of the basket before power-
linecontact, and b)stay inthe basketwith-
outtouching anything metal untilthe elec-
tricityis off for certain (the exceptionhere
being afire on board, which gives no other
alternative but bailingout). In researching
thissubject, older manuals, articles, anec-
dotes and seminars have generally taught
to get out of the basket before powerline
contact, while newer ones stressstaying in
the basket without touching metal. I per-
sonally favor the latter, but again, circum-
stances are different ineveryincident, and
the pilotincommandmust make that deci-
sion in quick order.
4) For the matter of pilot experience
vs.accident-proneness,please rereadmy
report inBalloon Lifeof September, 1993,
entitled“Isthereacorrelationbetween
pilot hours and accidents? The AIBF expe-
rience.” This report was based on 14 acci-
dents in 16,422 balloonflights occupying
24,640 ballooning hours, in 2318 balloons
BalloonLife,December 2000
and with 2963 pilots, 1989-92.My re-
search suggeststhat, after beingappropri-
atelycertifiedand ratedbythe FAA,num-
ber of pilothours in balloons has nothing
to do with having accidents. Others may
have different data, but so far no one has
published information to the contrary to
my knowledge. In addition, upon careful
inspectionof allthe data surroundingthis
incident, once the landing decision was
made, my opinion is that this pilot made
allthe correctdecisions. The one possible
exception (remaining inthebasketin-
steadofgetting out) hasalreadybeen
discussed.
5)I findseriousfaultwitha commer-
cial balloonist, with six years experience
and300+ hours ofballoon time,who
would have touched any balloon about to
gointoapowerline. Thisballoonistseemed
to be disregarding every tenet of his own
instruction and experience,and of con-
tinuing ballooning education; wemust
assume he was reading the general bal-
looninginformationpublishedatthetime,
doingdebriefingsof his own flights, hav-
ing tailgate talks with other balloonists,
and attending some seminars, as well as
accumulatinggeneral common sense. He
knew thisparticular balloon very well(he
had sold thisballoon to the pilot in com-
mand about twoyears beforethe inci-
dent),and knowing some thing about elec-
tricity(he was a general contractor aswell
asaballoonist),he should not have grabbed
the balloon (the metal uprights, in this
case) in order to stop it’s movement (he
weighed 140pounds, andwould have had
almost negligent effect on a balloon of
three plus tons of mass), and he should
have let go when the pilot told him to
(twice),and he shouldhave then helped to
keep others away from the balloon. This
“rescuer” said he rushed over to the bal-
loon because he feared the pilot in com-
mand may not have known about the
close proximity to the powerlines, and he
admitted he held on to“save”the pilot and
passenger. The pilot and passenger were
safer in the balloon than anyone standing
on the ground, holding on to any portion
of the basket, letalone themetaluprights.
One always assumes that a balloon has a
pyrometer wire, or that the combination
of the voltage/amperage of the powerline
and the moist and/or dirty nylon, isenough
to carve an electrical trail from “hot” to
ground. Also, this balloonist is lucky to
have had his life saved by the pilot in
command. The boomerang effect not only
brought the balloon back into the power-
lines, but nearly cost this fellow his life.
powerline, and this one is not weather-
related.In two cases I have studied,a
groundcrewcarrieda balloonintopower-
lines, one in Texas, and one in Colorado.
Pilots must be aware of this possibility
also, and take every precautionagainst it,
including vigorous crew briefing.
This incident occurred in 1993, and
yet litigation held up writing this story
until now.Thestonewall ofpending
litigation, with it’s lawyer-or court-in-
duced silence, or sometimes an insurance
companygagorder,is aproblemthat
limits safety instructors with sharing in-
formation with other balloonists as soon
as it becomes available. I have also had
pilotswho will not cooperate in detailing
accidents, most likely due to embarrass-
mentor possibleproblemswith the FAA,
insurance companies or others. Most pi-
lots however,cooperatefully inthese
investigations,becausetheyknowthe
excellent opportunities of learning from
others’ problems. This subject in general
was presented at the Albuquerque Aero-
stat Ascension Association Safety Semi-
nar heldOctober5, 1999,and again March
11, 2000 in Parker, Colorado for the Colo-
radoBalloonAssociation,butthefull
details of this case are given here for the
first time. I am indebted to Clarke O’Byrne
for critical comments regarding microme-
teorology.
