TheEconomistJanuary29th 2022 Science&technology 67
whichcantakeoverinordertolandit inan
emergency.Ithasa rangeof35kmbetween
charges,anda topspeedof130kph.
EHanghasformedpartnershipsfortrial
flightsinseveralcities,includingGuang
zhouinsouthernChina,wherethefirmis
based.Oncea typecertificateisobtained,
thecompany plans to offercommercial
airtaxiandsightseeingflightsfromthese
places,alongwithparceldeliveries.
Crossingcontinents
Forevtols tooperatecommerciallyandat
scaleinmostcountries,threekindsofreg
ulatoryapprovalwillberequired,saysJen
niferTrock,whoisbasedinWashington,
dc,andleadstheaviationpracticeofBaker
McKenzie,a lawfirm.Besidesa typecertif
icate,firmswillalsoneedproductioncerti
fication,whichpermitsmanufacturingof
anaircrafttobeginatvolume.And,inor
dertocarryfarepayingpassengers,anair
linestyleoperatinglicenceisrequired.
Thoughtherearebilateralsafetyagree
mentsbetweeneasa,caacandAmerica’s
FederalAviationAdministration(faa), the
threeagencieswhichdominatetheworld’s
aviationmarket,certificationbyonedoes
notautomaticallyapplyelsewhere,espe
ciallyfornewdesignslikeevtols.This,
saysMsTrock,givesmakerstwooptionsif
theywishtoselltheiraircraftinanother
market.Theycansetupa localoperation
andapplyforanothercertificate,asAuto
Flightisdoing.Ortheycansubmittoa full
technicalvalidationofthecertificatethey
haveobtainedinanothercountry,though
thismightinvolvefurthertestflights.
Thereisalsouncertaintyabouthowthe
ruleswilldifferfromplacetoplace.After
examiningsome 150 designs,easa con
cluded that evtols were neither aero
planes,norhelicopters,norboth.Itthere
foredecidedtomakethema “specialcate
gory”ofaircraft,withtheirownsetofregu
lations.Thefaa, bycontrast,saysitcan
certifythembytailoringitsexistingrules
wherenecessary.Ithassetupa unitcalled
theCentreforEmergingConceptsandIn
novationtoworkwithevtolcompaniesto
establishdetailedsafetyrequirements.
Nonetheless, enough regulatory pro
gresshasbeenmadeforevtolpioneersto
remainoptimistic.InAmerica,JobyAvia
tionhopesnextyeartobecomethefirstto
obtaintypecertificationfromthefaa. Itis
makinga dozenormoreaircraftata new
manufacturing plant inMarina, Califor
nia, to step up its flighttesting pro
gramme.Joby’sairtaxi,whichseatsfour
passengersanda pilot,usesmultiplero
torstotakeoffandland.It thentiltsthero
torsforwardwhencruising,sotheywork
likepropellers.Oneofthecompany’sback
ersisUber,a firmthatcurrentlymakesits
moneyorganisingterrestrialtaxirides.
HotonJoby’sheelsisArcherAviation,
alsoCalifornian.Archerplansa commer
cialridesharingserviceusinga fourpas
sengerspluspilotdesign,tostartin2024.
OneofitsinvestorsisUnitedAirlines.In
Europe,Volocopter,a Germanfirm,istest
inga multirotorevtolinbothcrewedand
uncrewedform.It hopestoprovideairtaxi
services forthe 2024 Olympicgamesin
Paris. Lilium, another German firm, is
workingonanallelectricsevenseater.
Anditisnotonlynewfirmswhichare
gettingintothebusiness.Airbusisdevel
opingideasforevtols.SoisBoeing,its
Americanrival.OnJanuary24th,Boeing
invested$450minWiskAero,ofSanFran
cisco,whichisdevelopingyetanotherau
tonomousevtol. LarryPage,a cofounder
ofGoogle,isbackingthisfirm,too.Withso
much effortandmoneygoing into this
newformofaviation,someofthesebirds
willsurelyfly.n
It’s a bird...it’s a plane...
Air-taxi investments*, $bn
Source: McKinsey
*Includes venture capital, attributed R&D
funding and announced SPAC mergers
5 4 3 2 1 0
Pre- 212019181716152014
2014
Dataprivacy
Your secret’s safe with me
D
ata arevaluable. But not all of them
are as valuable as they could be. Rea
sons of confidentiality mean that many
medical, financial, educational and other
personal records, from the analysis of
which much public good could be derived,
are in practice unavailable. A lot of com
mercial data are similarly sequestered. For
example, firms have more granular and
timely information on the economy than
governments can obtain from surveys. But
such intelligence would be useful to rivals.
If companies could be certain it would re
main secret, they might be more willing to
make it available to officialdom.
A range of novel dataprocessing tech
niques might make such sharing possible.
These socalled privacyenhancing tech
nologies (pets) are still in the early stages
of development. But they are about to get a
boost from a project launched by the Unit
ed Nations’ statistics division. The un pets
Lab, which opened for business officially
on January 25th, enables national statistics
offices, academic researchers and compa
nies to collaborate to carry out projects
which will test various pets, permitting
technical and administrative hiccups to be
identified and overcome.
The first such effort, which actually be
gan last summer, before the pets Lab’s for
mal inauguration, analysed import and ex
port data from national statistical offices
in America, Britain, Canada, Italy and the
Netherlands, to look for anomalies. Those
could be a result of fraud, of faulty record
keeping or of innocuous reexporting.
For the pilot scheme, the researchers
used categories already in the public do
main—in this case international trade in
things such as wood pulp and clocks. They
thus hoped to show that the system would
work, before applying it to information
where confidentiality matters.
They put several kinds of pets through
their paces. In one trial, OpenMined, a
charity based in Oxford, tested a technique
called secure multiparty computation
(smpc). This approach involves the data to
be analysed being encrypted by their keep
er and staying on the premises. The organi
sation running the analysis (in this case
OpenMined) sends its algorithm to the
keeper, who runs it on the encrypted data.
That is mathematically complex, but pos
sible. The findings are then sent back to the
original inquirer.
That inquirer thus receives its answers,
but never has access to the information on
which those answers are based. Moreover,
for extra security, the results are processed
by another pet, called differential privacy.
This employs elaborate maths to add a
smidgen of statistical noise to a result.
That makes the findings less precise, but
means they cannot be reverseengineered
to reveal individual records. It also permits
the organisation releasing the findings to
set a socalled “privacy budget”, which de
termines the level of granularity disclosed
by the data. The result is a beltandbraces
approach. In the argot of the field, smpc
provides input privacy, while differential
privacy offers output privacy.
The unis testing new technology that processes data confidentially