August

NASA/

Eme

Aero

Dennis M

Langley R

t 2012 

/TM–201

erging 

onautic

M. Bushnell 

Research Ce

2-217759

Option

cs 

enter, Hamp

9

ns and

pton, Virginia

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Aero

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Langley R

Aeronautics and

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esearch Center

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2-217759

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enter, Hamp

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pton, Virginia

 Opportunities in Civilian 
Available from: 

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443-757-5802 
1	

Emerging	Options	and	Opportunities	in	Civilian	Aeronautics	

Dennis	M.	Bushnell	

Abstract	

		Paper	address	the	major	problems/issues	with	civilian	aeronautics	

going	forward,	the	contextual	ongoing	technology	revolutions,	the	

several	emerging	civilian	aeronautical	“Big	Ideas”	and	associated	

enabling	technological	approaches.	The	ongoing	IT	Revolution	is

increasingly	providing,	as	5	senses	virtual	presence/reality	becomes	

available,	along	with	Nano/Molecular	Manufacturing,	virtual	

alternatives	to	Physical	transportation	for	both	people	and	goods.	Paper	

examines	the	potential	options	available	to	aeronautics	to	maintain	and	

perhaps	grow	“market	share”	in	the	context	of	this	evolving	

competition.	Many	of	these	concepts	are	not	new,	but	the	emerging	

technology	landscape	is	enhancing	their	viability	and	marketability.	The	

concepts	vary	from	the	“interesting”	to	the	truly	revolutionary	and	all	

require	considerable	research.	Paper	considers	the	speed	range	from	

personal/general	aviation	to	supersonic	transports	and	technologies	

from	energetics	to	fabrication.	

Introduction	

	Civilian	Aeronautics	is	currently	pursuing	a	self‐fulfilling	prophecy,	

becoming	a	“mature”	commodity	Industry.	Advancements	have	been	

essentially	incremental	for	decades.	This	incrementalism	is	in	fact	

“usual”	as	an	industry	matures.	Aeronautics	was	a	technological	“fast‐

mover”	in	the	mid	20th	century	with	many	“players”,	most	of	which	have	

merged	or	gone	out	of	business.	New	products	can	be	a	“bet	the	

company”	situation	and	the	industry	is	currently	far	more	“comfortable”	

with	long	technology	maturation	processes	for	risk	reduction.	The	

industry	is	based	largely	upon	long	haul	transport	aircraft	with	an	

emerging	small	jet	component	and	legacy	general	aviation	markets	and	

products.	

		
2	

Civilian Aeronautics in the U.S. is at a crucial crossroads. At one time and 

over an extensive period (from the ‘20’s into the ‘70’s) aeronautics was one 

of the “IT/Bio/Nano” class technology revolutions of the day with a frontier 

credo of higher/faster/farther. Aeronautics was deemed to be so critical to 

the national well-being that it became one of the very few industrial arenas 

wherein fundamental, advanced and pre-competitive research was supported 

by the federal government (others include National Defense, 

pharmaceuticals and agriculture). Many studies exist justifying this special 

status, as it is, understandably, under continuous scrutiny. Today and into 

the foreseeable future aeronautics is beset with a wide spectrum of problems 

which the IT, Nano and other ongoing and nascent technological revolutions 

will both potentially aggravate these problems and enable truly 

Revolutionary “solution spaces.” This treatise will examine and comment 

on both the prospective problem and potential solution spectrum/ spaces 

going forward. 

 It is interesting to note that many of the various Aeronautical goals 

addressed in this report are called out in Ref. 59, the 2010 update to the U.S. 

National Aeronautics R&D plan from the National Science and Technology 

Council. These include an advanced ATC system enabling UAS in the NAS, 

increased L/D and innovative Structural Concepts, and decreasing 

Aeronautical Environmental impacts, among many others. The concepts 

addressed in the present report, individually and/or combinatorially are in 

general beyond the current extant Aeronautical R&D approaches. 

The	Civil	Aeronautics	“Problems”	

Continuing	Loss	of	U.S.	Market	Share	–	The	world	has	long	changed	from	

the	immediate	post	WW	II	scenario	of	U.S.	technological	dominance.		To	

first	order,	research	is	the	order	of	2%	of	gross	domestic	product	(GDP)	

and	the	U.S.	produces	the	order	of	20%	(and	dropping)	of	the	Worlds’	

GDP.		Therefore,	a	major	[~	70%]	and	increasing	portion	of	the	Worlds’	

research	is	now	conducted	outside	of	the	U.S.		Also,	the	deployed	civilian	

aeronautical	technology	tended	toward	evolutionary	(as	opposed	to	

revolutionary)	by	the	end	of	the	1970’s	and	some	U.S.	competitors	have,	

in	some	cases,	been	more	aggressive	in	fielding	advanced,	evolutionary	

technologies.	Civilian	aeronautics,	based	upon	the	deployed	technology,	

became	more	of	a	mature,	commodity	industry	with	many	current	and	

potential	foreign	players.		Extensive	studies	have	documented	long	

running	reductions	in	U.S.	Market	share	for	transport/other	aircraft.		
3	

Other	factors	impacting	civilian	aeronautics	market	share	include	

business/technology	“globalization”	and	the	secondary	effects	of	the	

end	of	the	cold	war/consequent	restructuring	of	the	related	military	

aeronautics	industry.		The	key	phrase/issue	in	all	of	this	is	“deployed	

technology.”		A	related	key	issue	is	an	unstated	but	assumed	restriction	

to	“the	usual	markets.”		Revolutionary	technologies	and	technology	

related	market	changes	could	greatly	impact	this	and	all	other	

aeronautical	problem	areas.		This	problem	is	of	course	exacerbated	by	

the	cyclic	nature	of	the	industry,	and	its’	importance	to	U.S.	macro‐

economics	as	aerospace	has	historically	constituted	the	largest

favorable	trade	balance	in	the	manufacturing	sector.			

Increasing	Acoustical	Strictures	–	For	decades	takeoff	(primarily	

propulsion‐related)	and	more	recently	landing	(primarily	airframe	

noise‐related)	acoustical	regulations	have	modified/restricted	both	

aircraft/engine	design	and	operation.		These	acoustic	regulations	tend	

to	change	so	as	to	correspond	to,	and	push,	the	technical	state‐of‐the‐

art.		What	the	public	evidently	would	really	desire	is	clear	–	“noiseless”	

(compared	to	the	nominal	“background”)	aircraft	operations.		Entire	

classes	of	aircraft,	notably	the	supersonic	transport	(SST),	have	been	

literally	“taken	off	the	design	table”	due	to	acoustic‐related	

issues/strictures.		In	the	National	Aeronautics	and	Space	Administration	

High	Speed	Research	(NASA	HSR)	program	a	pound	of	weight	on	the

HUGE	mixer‐ejector	required	to	suppress	takeoff	jet	noise	corresponded	

to	the	order	of	some	32	pounds	of	takeoff	weight	–	severely	

compromising	the	overall	design.		As	the	population	has	moved	outward	

to	engulf	airports,	many	of	which	were	initially	located	in	sparsely	

populated	regions,	the	Aeronautical	noise‐related	problems/resultant	

societal	“upsetness”	has	become	aggravated.		Acoustics	is	a	major	

reason	for	the	inordinately	long	(decades	in	some	cases)	periods	

required	to	construct	new	airports	or	carryout	major	modifications	

thereof.		Some	airports	have	even	instituted	noise‐engendered	

“curfews”	for	aircraft	operations/schedules.		

Increasing	Environmental	Strictures	–	After	several	decades	of	concerns	

and	warnings	global	warming	appears	to	have	changed	from	a	

theoretical	possibility	to	a	measurable	reality.		Societal	response	is	

becoming	decreasingly	one	of	denial	but	major	societal	and	

technological	changes	have	not	yet	been	instituted,	due	primarily	to	
4	

their	overarching	impacts	upon	life‐styles	and	economics.		Society	as	a	

whole	is	obviously	still	in	“denial”	regarding	what	needs	to	be	done,	

both	in	terms	of	regulatory	strictures	and	whole	new	classes	of

technologies.		However,	this	state	of	denial	(driven	by	the	inexorable	

laws	of	physics,	chemistry	and	thermodynamics)		will	change	at	some	

point	into	action;	actions	which	will	affect	aeronautics	as	well	as	every	

other	energy	utilization	industry	and	activity.		Currently	aviation	is	

studying	ways	and	means	to	reduce	Carbon	Dioxide	(CO2)	and	Nitrogen	

Oxides	(NOx),	including	use	of	biofuels	as	well	as	aircraft	efficiency.		

However,	scientific	studies	indicate	that	an	additional	potentially	

significant	“warming”	problem	involving	aeronautics	operations	may	be	

the	deposition	of	water	vapor	(yet	another	result	of	the	open	cycle	

combustion	of	Hydrocarbons)	above	~27,000	feet	[	The	Tropopause],	

leading	to	the	formation	of	extensive	Cirrus	clouds	and	further	changes	

in	the	Earth’s	Albedo/“warming.”		The	ultimate	solution	to	all	of	this	

would	be	to	utilize	“emissionless”	propulsion.		Some	Nations	are	already	

considering	the	institution	of	a	“carbon	tax,”	which	would,	as	a	

minimum,	increase	the	costs	of	aircraft	operation.	

Aging/Aged	Air	Traffic	Control	System	–	The	problems	with	the	air	

traffic	control	(ATC)	system	are	at	this	point	infamous.	Estimates	of	the	

cost	to	the	U.S.	economy	of	airport/airspace	congestion	are	in	the	

billions.		In	one	month	there	were	purportedly	some	100	major	

problems	in/with	the	system.		There	are	clarion	calls,	and	current	on‐

going	studies	to	“fix”	the	system.		An	additional	major/paradigm‐

changing	requirement	is	the	increasing	necessity	to	accommodate

military,	DHS	(and	later	civilian)	automatic‐to‐autonomous	air	vehicles	[	

AKA	UAS]	in	“controlled”	air	space.		Congress	is	pushing	hard,	for	a	

myriad	of	very	valid	reasons,	to	have	a	major	portion	of	military	air	

vehicles	‘uninhabited”	and	military	planning	is	also	working	in	this	

direction.		The	current	ATC	system	is	highly	labor	intensive	and	

therefore	costly.	

Aviation	Security	–	The	infamous	9/11	incident	involving	the	high‐

jacking	and	subsequent	use	as	cruise	missiles	of	commercial	aircraft	

along	with	the	overall	suite	of	potential	aviation‐related	terrorist	

threats	have	greatly	increased	concern	regarding	aeronautical	security.		

What	is	ultimately	required	is	far	more	than	merely	keeping	“bad	

people	and	bad	things”	off	of	aircraft—although	this	is	an	obvious	place	
5	

to	start	working	the	problem.	An	emerging	“security”	problem	is

electro‐magnetic	pulse	[EMP].	Flux	compression	generators	powered	by	

explosives	or	capacitors	are	increasingly	capable	of	interfering‐to‐

obviating	installed	electronics.	Such	devices	could	be	either	delivered	by	

missile	or	activated	on	the	ground	during	landing/	takeoff.	Fear	of	being	

involved	in	security	incidents	along	with	the	consequent	increase	in	

security‐related	passenger	“hassle‐factor”	at	airports	have	contributed	

to	some	of	the	traveling	public,	both	business	and	private,	finding	other	

methods	of	either	traveling	or	conducting	their	business.		Much	of	

airline	operations	involve	relatively	short	(less	than	500	miles)	trips,	

and	people	are	using	surface	transport	more	often	for	these	short	stage	

lengths.		Also,	the	increasing	capabilities	of	various	forms	of	electronic	

communications	have	enabled	substitution	of	virtual	for	physical	travel	

in	an	increasing	number	of	cases.	The	author	recently	gave	a	

presentation	in	New	Zealand	virtually	as	opposed	to	the	many	days	and	

dollars	associated	with	transpac	physical	travel/	presentation.

Virtual/Tele‐Living	writ	large	[commuting/working,	shopping,	travel,	

education,	commerce	etc.]	appears	to	be	one	of	the	reasons	for	the	

decline	in	U.S.	vehicle	miles	traveled	on	the	roads.	Some	are	asking	

whether	the	U.S.	has	reached	“peak	car”.	

Aviation	Safety	–	This	problem	area	actually	has	an	excellent	outlook.	

Some	80%	or	so	of	aviation	safety	problems	involve	human	actions	in	

some	form,	including	“controlled	flight	into	terrain”–	aka,	flying	into	the	

ground.		The	overall	accident	rate/hull	loss	statistics	are	much	lower	

than	other	forms	of	transportation	–	automobiles	for	example,	and	there	

are	a	myriad	of	relatively	straight‐forward	technology	“fixes”	in	the	

works	to	drive	the	accident	rates	even	lower.		Ultimately,	the	major	

trends	(enabled	by	the	IT/Nano	technology	revolutions)	toward	

automatic/robotic	operation	and	automatic	health	monitoring	should	

decrease	the	“human‐related”	causes	of	accidents	by	getting	the	humans	

out	of	the	loop.		In	fact,	“getting	the	humans	out”	as	a	general	approach	

should	also	result	in	increasingly	major	cost	reductions	as	people‐

related	expenses	are	a	major	portion	of	direct	operating	costs	and	

“electron‐related”	systems	and	robotics	are	rapidly	becoming	

smaller/cheaper/smarter/lighter	as	well	as	increasingly	reliable.	

Radiation	–	There	are	two	major	sources	of	radiation	incident	upon	the	

Earth,	galactic	cosmic	radiation	and	solar	engendered.		This	radiation	is	
6	

modified	by	the	geomagnetic	field	and	the	Earth’s	atmosphere.		As	an	

example,	purportedly	the	ambient	radiation	at	cruise	altitude	for	

conventional	long	haul	transports	is	some	100	times	normal	ground	

background	levels.		The	Radiation	of	concern	for	aircraft	crew	and	

passengers	peaks	at	around	60,000	feet,	the	nominal	cruise	altitude	for	

SST’s.		Airline	crew	are	now	classified	as	“radiation	workers”	and	tend	

to	accrue	higher	doses	than	nuclear	power	plant	workers.		A	rule‐of‐

thumb	is	that	a	4,000	mile	flight	is	the	order	of	a	chest	X‐ray	(each	way).		

This	is,	however,	evidently	not	a	major	worry	for	usual	passenger	travel	

as	the	overall	percentage	of	time	spent	in	the	air	is	not	large.		The	safest	

place	radiation‐wise	to	sit	appears	to	be	on	the	aisle	in	the	economy	

section	where	the	other	water‐filled	humans	tend	to	absorb	some	of	the	

radiation	before	it	reaches	you.		The	current	structural	materials	such	as	

aluminum	tend	to	increase	the	levels	inside	the	cabin	due	to	interaction	

with	the	incident	radiation	/	production	of	secondary	radiation..		The	

main	risk	is	to	the	crew	due	to	their	many	hours	at	cruise	altitudes.	

Increasingly	Serious	(Non‐Aeronautical)	Competition	–	There	have	been	

several	suggestions	over	the	years	that	various	forms	of	communication	

could‐to‐would	provide	viable	alternatives	to	physical	travel.		A	study	in	

the	mid‐nineties	by	the	Transportation	Research	Board	suggested	that	

by	2015	this	could	cause	a	loss	of	some	40%	of	the	(profit‐producing)	

business	travelers.		There	has	been	some	observable	trends	in	this	

direction	but	nothing	major	thus	far.		However,	the	available	virtual	

competition	(to	this	point)	has	usually	been	restricted	to	flat	screens	

and	a	combination	of	sight	and	sound.		As	the	huge	bandwidth	increases	

of	optical	communications	become	very	widely	available	other,	far	more	

immersive,	non‐physical	“travel”	will	become	available	–	virtual	reality	

and	holographic	projection,	either	synchronous	or	asynchronous.		

Haptic	touch	has	been	demonstrated	across	the	Atlantic	and	a	virtual	

smell	approach	has	been	patented.	5	senses	virtual	reality	has	been	

commercially	demonstrated.	Increasingly	time	is	the	critical	parameter,	

and	“saving”	time	is	goodness.		Increasingly	this	is	not	a	subsonic	vs.	

supersonic	transport	issue	‐	this	is	a	physical	transport	vs.	the	speed	of	

light/	virtual	presence	issue.		As	immersive	presence	experience	

becomes	“really	good	and	complete”	it	will	often	“win	out”	for	time	as	

well	as	cost	saving	reasons.	
7	

Exclusivity	of	General	Aviation	–	The	“airplane	in	every	garage”	and	

various	flavors	of	personal	combined	fly/drive	machines	envisaged	over	

the	years	never	became	feasible	for	a	number	of	reasons	including	an	

absolute	requirement	for	an	“operator‐pilot.”		There	are	relatively	few	

within	the	general	population	who	have	the	time,	health	and	treasure	to	

become	pilots.		Therefore,	the	market	never	became	large	enough	to	

accrue	the	additional	factor	of	8	or	so	cost	reduction	from	

“mass/quantity	production.”		General	aviation	(private	and	business),	

which	accounts	for,	by	far,	most	of	the	airports	and	aircraft	in	terms	of	

numbers	has	remained	a	“rich	man’s	toy”	requiring	resources	in	excess	

of	those	available	to	the	general	population.		The	nascent	“personal	

aircraft”	market	is	HUGE,	with	estimates	ranging	up	to	$1T/year

Worldwide	–	far	larger	than	the	current	transport	aircraft	markets	in	

the	U.S.		A	market	which	could,	if	successfully	attained,	revolutionize	

societal	life	styles,	land	use,	national‐to‐international	economics	as	well	

as,	on	the	way,	“fix	aeronautics.”		Such	personal	aircraft,	particularly	if	of	

the	fly/drive/	short	take	off	and	landing	(VSTOL)	genre	with	reasonable	

(300+	knots)	capability	would,	for	many	reasons,	provide	serious	

competition	to	domestic	commercial	airline	transportation	–	the	“PC”	

version	of	aviation	vs.	the	current	“mainframe”	(commercial	transport)	

paradigm,	as	well	as	competition	and	infrastructure	cost	avoidance	wrt	

the	automobile	market.	

Declining	Business	Case	–	The	civilian	aeronautics	profit	margins	are	

notoriously	small‐to‐negative.	This	situation	could	worsen	as	solutions	

are	sought	to	many	of	the	problem	areas	cited	herein	within	the	context	

of	the	current	deployed	evolutionary	technology	suites.		Additionally,	

there	are	exquisite	sensitivities,	engendered	by	the	slim	profit	margins,	

to	various	mutable	costs	of	doing	business	such	as	fuel	price.		A	major	

reason	for	the	current	business	state	is	the	asymptotic/“mature”	nature	

of	the	deployed	technology.		The	gains	in	aircraft	performance	over	the	

past	decades,	especially	in	terms	of	fuel	efficiency	and	noise	reduction,	

are	mainly	a	result	of	increased	engine	bypass	ratio.		Aerodynamic	

performance	improvements	have	been	minimal.	Serious	attempts	to

improve	aerodynamics	via	laminar	flow	control	encountered	

affordability	difficulties.	Therefore,	there	is	little	current	or	foreseeable	

“design	margin”	(with	the	current	deployed	technology	suite)	which	

would	evidently	allow	the	industry	to	holistically,	across	the	spectrum	

of	problem	areas	discussed	herein	”get	well”	and	successfully	compete	
8	

with	the	emerging	tele/virtual	travel	alternatives.	The	cost	comparison	

between	these	two	options	is	highly	unfavorable	to	aeronautics	and	the	

emerging	technologies	are	expected	to	provide	seriously	capable	virtual	

presence.	The	newer	generation	grew	up	on	/using	electrons/	

electronics,	are	already	entering	the	‘Virtual	Age”.	

			There	has	been	a	reduction	in	short	haul	aviation	traffic	which	may	be	

due	to	one	or	[probably]	several	of	the	following:		

‐ Driving	is	cheaper	

‐ 	Increased	Virtual/tele‐travel	utilization	

‐ The	Economic	downturn	

‐ The	actual	total	effective	trip	time,	with	the	necessity	to	arrive	

early	at	the	terminal	and	rent	cars	etc.	upon	arrival	at	an	airport	

can	be	less	driving	vice	flying	

‐ Changes	in	airline	service	schedules/	availability	

																									The	Emerging	Technological	Landscape	

		

	We	are	currently	in	the	midst	of	a	major	wide	spectrum	Technological	

Revolution	including	IT,	Bio,	Nano,	Energetics	and	Quantum	

Technologies.	These	technologies	are	altering	in	real	time	the	entire	

panoply	of	human	activities,	including	Aeronautics.	The	purpose	of	this	

report	is	to	consider	the	potential	implications	of	these	rapid	technology	

changes	upon	both	Aeronautical	Functionalities/	Markets	and	the

detailed	manner	in	which	we	execute/realize	those	functionalities	[	e.g.	

both	what	aeronautics	does	in	the	future	and	how	it	does	it].	

		IT	‐	We	have	improved	computing,	on	silicon,	some	7	to	8	orders	of	

magnitude	since	’59,	the	~	15	petaflop	human	brain	speed	machine	was	

delivered	in	2012.	Going	forward	we	will	go	beyond	silicon	to	bio,	

optical,		nano,	molecular	and	atomic	computing	with	estimates	of	some	

8	to	12	orders	of	magnitude	still	to	be	realized	over	the	next	decades.	

Then	there	is	Quantum	Computing,	which	for	an	increasing	number	of	

applications	is	projected	to	provide	up	to	44	orders	of	magnitude	

improvement	and	is	envisaged	by	some	to	be	less	than	2	decades	in	the	

future.	Thus	far	in	the	discussion	this	is	just	raw	speed.	Machine	

Intelligence	approaching	human	level	is	being	worked	via	Soft	

Computing	[neural	nets,	fuzzy	logic,	genetic	algorithms	etc],	

Biomimmetics	and	perhaps	Emergence,	the	latter	is	the	probable	

manner	by	which	humans	developed	“Intelligence”	‐	make	something	
9	

complex	enough	and	it	“wakes	up”.	Presently	Biomimmetics,	

nanosectioning	the	brain	and	replicating	it	in	silicon,	appears	to	be	the	

foremost	approach,	with	the	IBM	Blue	Brain	Project	suggesting	human	

level	or	nearly	so	machines	at	some	10‐15	years	out.	In	the	runup	

Machine	Intelligence	is	becoming	increasingly	“useful”/	capable.		

		These	massive	improvements	in	IT	capability	are	changing	society	

greatly,	enabling	increasingly	“Tele‐everything”	–	Tele	

commuting/work,	shopping,	travel,	education,	medicine,	commerce,	

politics,	socialization,	etc....	This	rapidly	developing	machine	capability	

has	produced	a	decades	long	shift	in	Aeronautical	testing/	product	

development	from	major	dependence	upon	wind	tunnels	to	increasing	

dependence	upon	Mod‐Sim	/	computation.	If/when	Quantum	

computing	is	developed	the	resulting	machine	capacity	would	probably	

enable	ab‐initio	computation	of	turbulence	in	a	design	mode,	resulting	

in	further	major	reductions	in	Wind	Tunnel	requirements.	The	tele‐

travel	estimates	have	long	projected	a	major	drop	in	aircraft	business	

travel	in	favor	of	tele‐travel	in	less	than	a	decade.	This	tele‐travel	would	

be	accomplished	via	the	increasingly	capable,	initial	versions	

demonstrated,	5	senses	virtual	reality,	haptic	taste,	touch,	smell,	sight	

and	sound.	Estimates	indicate	that	many	millions	worldwide	are	

spending	now,	on	flat	screens,	more	time	in	virtual	worlds	than	in	the	

“real	world”.	This	is	expected	to	greatly	increase	as	first	virtual	reality	

and	then	5	senses	virtual	reality	become	available	with	serious	fidelity.	

From	this	discussion	–	possibly	fewer	airline	travelers	rather	than	the	

large	increases	in	numbers	previously	projected.	Ridership	is	already	

less	than	earlier	extrapolations,	possibly	due	to	a	combination	of	the	

economic	conditions	and	the	improvements	in	tele‐travel.	

		The	evolving	IT	technologies	also	proffer	the	real	possibility	of	a	much	

more	capable	and	far	less	expensive	Air	Traffic	Control	[	

ATC]/Navigation/Operations	system	enabling	Uninhabited	Air	Systems	

[UAS]	in	controlled	airspace	for	Military,	DHS	and		Civilian	use.		Such	a	

system	could	be	developed	and	proven	out	piecemeal	via	operation	

parallel	to	the	existing	system	with	no	operational	utilization,	just	

experimental	studies,	until	the	entire	new	system	is	fully	vetted.	There	

are	emerging	technologies	potentially	capable	of	providing	triply	

redundant	fail	safe‐safe	communications,	navigation,	sensors	and	

computing,	along	with	the	DOD	swarm	technologies	studies.	These
10	

technologies	include	“Atom	Optics”	[Inertial	Navigation	Systems	with	

many	orders	of	magnitude	improvements],	and	passive	

location/navigation	using	the	TV	tower	signals	with	many	orders	of	

magnitude	greater	signal	amplitude	than	GPS.	Hal	Puthoff	has	a	

vector/scalar	potential	approach	that	could	revolutionize	

communications,	and	optical	free	space	communications	are	developing	

nicely.	Then	there	is	the	emerging	“Global	Sensor	Grid”,	thanks	to	low	

energy	improved/inexpensive	nano	and	quantum	sensors.		The	

projections	indicate	networking	of	vast	numbers	of	sensors,	producing	a	

“Digital	Air	Space”	some	decade	plus	out.	Such	a	“beyond	Next‐Gen”	ATC	

etc.	system	would	enable	the	deployment	of	both	civilian	robotic	

delivery	vehicles	and	UAS	carrying	passengers,	i.e.	PAVE	or	Personal	Air	

Vehicles.	Such	vehicles	could	be	both	affordable	and	safe,	allow	Aero	to	

usurp	some‐to‐much	of	the	automobile	markets	and	enable	cost	

avoidance	for	some	of	the	surface	transportation	infrastructure.	The	

vehicles	for	PAVE	are	under	development,	a	goodly	number	are	given	at	

www.	roadabletimes.com.	The	estimated	PAVE	worldwide	Aero	

Markets,	with	parts,	is	in	the	range	of	$1T/	year,	far	greater	than	the	

current	civilian	Aeronautical	level.	As	PAVE	vehicles	are	envisaged	to	be	

autonomously	operated	they	could	be	utilized	by	the	aged,	the	infirm,	

the	young	and	the	inebriated.	PAVE	is	the	“Personal	Computer”version	

of	Aeronautics	and	has	shown	great	robustness	in	terms	of	“market”/	

population	desirement	for	nearly	a	century.	We	are	now	quite	close	to	

the	requisite	technologies.	

		“The	Roads	to	support	Autos	cost	as	much	as	a	small	war	and	the	

casualties	are	on	the	same	scale”	

		Arthur	C.	Clark,	1984	

		With	the	availability	of	appropriate	ATC	etc.	systems,	Robotic	Delivery	

vehicles	and	PAVE	the	population	could	expand	in	terms	of	land	use	to	a	

much	lower	density,	adopting	at	the	same	time	a	Toflerian	Prosumer	

status.	We	have	some	200,000	off	the	[electric]	grid	homes	now	and	

some,	an	increasing	number,	are	going	off	ALL	the	grids	[	electric,	water,	

sewage,	food]	as	the	technology	is	enabling	such	and	tele‐living	

becomes	more	pervasive.	Simplex	estimates	indicate,	as	an	example,	a	

factor	of	up	to	50	less	overall	environmental	impact	from	tele‐shopping	

as	opposed	to	physical	shopping.	Autonomous	/robotic	operation	of	
11	

both	vehicles	and	the	ATC	system	should	be	both	far	less	expensive	and	

significantly	“safer”	as	some	80%	of	aviation	accidents	are	ascribed	to	

“Human	Error”.	

		IT	also,	via	Mod‐Sim,	enables	design	of	ultra	efficient	Aero	

Configurations	at	R&D	costs	far	less	than	the	Industrial	Age	methods	

involving	significant	physical	testing.	A	current	near	best	bet	transport	

concept	appears	to	be	externally	truss‐braced	wings	enabling	thinner	

wings	and	reduced	wing	sweep	for	natural	laminar	flow	and	greatly	

increased	span	for	decimation	of	drag‐due‐to‐lift.	If	the	engines	are	

placed	at	the	rear	of	the	fuselage	and	thrust	vectored	for	control	then	

the	empannage	weight	and	drag	can	be	obviated.	Additionally	a	

Goldschmied	Cowl	around	the	engine	proffers	the	possibility	of	

favorable	propulsive/	airframe	interference	and	provides	internal	

volume	for	noise	treatments.	Then	there	is	fuselage	[re]	laminarization.	

The	lift	to	drag	ratio	of	such	a	transport	design	is	in	the	40’s	plus	[	

Pfenninger	designed	one	with		lift‐to‐drag	ratio	[	L/D]	~	100]	with	

major	[	perhaps	as	much	as	80%+	]	fuel	burn	reductions.	Mod‐Sim	also	

would	enable	Channel	wings	with	circulation	control,	an	interesting	

super	short	takeoff	and	landing	approach.	An	alternative	configuration	

approach	having	“Sky	Train”/	“Modular	Aircraft”	functionality	is	a	

double	fuselage/	mid	[unswept]	Natural	Laminar	Flow	wing	concept	

with	the	wing	tip	fuselages	optimized	for	drag‐due‐to‐lift	reduction	

including	the	engines	positioned	at	the	rear	of	the	fuselage[s].	Fuselages	

are	“interchangeable”	for	optimized	operation	tempo/	overall	system	

efficiency.	Mod‐Sim	would	also	enable	serious	study	of	a	Transonic	Bi‐

Plane,	with	a	tentative	performance	improvement	greater	than	25%.	

For	Super	short	takeoff	and	landing	capability	Mod‐Sim	enables	

synergistic	design	of	a	Channel	wing	with	Circulation	control	–

providing	a	near	theoretical	4	Pi	optimal	lift	coefficient.	The	massive	

supersonic	transport	improvements	from	the	Pfenninger	strut	braced	

extreme	arrow	wing	design,	with	L/D	values	of	order	16	vice	9	ish	for	

conventional	configurations	are	also	now	within	reach	courtesy	of	Mod‐

Sim,	as	are	favorable	wave	interference	supersonic	designs	[	again	order	

of	25%ish	improvements],	wave	rotors	for	major	overall	improvements	

in	GTEs	and	ring	wings	of	various	flavors.	

		Sir	James	Lighthill	once	told	the	author	“We	build	what	we	can	

compute”	and	this	constrained	us	for	far	too	long	to	nearly	linear	
12	

theories	and	consequent	linear	thinking/	conceptualization.	The	IT	

engendered	Mod‐Sim	has	opened	up	the	configuration	design	spaces	to	

include	“open	Thermodynamic	systems”	where	the	propulsive	and	

aerodynamic	functions	are	synergistically	combined,	along	with	such	

enabling	structural	concepts	as	external	strut/truss	bracing	–	a	further	

gift	of	Mod‐Sim	in	terms	of	interference	drag	minimization.	Pulse	

detonation	wave	engines,	where	the	wave	dynamics	is	tailored	to

provide	valving	and	ignition,	along	with	anti‐noise,	would	enable	a	

much	less	expensive	propulsion	device	

Nano	‐	Nano	materials	are	projected	to	have	major	impacts	upon	

structural	weight	across	the	board.	These	are	developing	with	various	

“flavors”	including	Carbon	Nano	tubes	[400	degrees	C],	Boron	Nitride	

Nano	tubes	[800	degrees	C],	Graphene	and	others.	Thus	far	these	have	

been	employed	in	composite	materials	but	there	are	efforts	underway	

to	produce	nano	tube	structures	directly.	If	successful	these	might	

potentially	reduce	dry	weight	some	factors	of	3	to	5	to	8,	not	

percentages,	factors	,	TBD.		Then	there	is	the	possibility	of	carbon	

nanotube	springs	with	estimated	performance	many	orders	of	

magnitude	better	than	steel	springs.	Applications	include	Superstol	

takeoff	and	landing	[employing	re‐generation],	providing	an	

opportunity	to	“Spring	into	the	air”.........	

		Then	there	is	“strong	Nano”,	the	original	Erik	Drexler	“Engines	of	

Creation”	Nano	where	“Mechanical	Engineering”	is	used	to	assemble	

materials	“Atom‐by‐Atom”	vice	the	current	largely	Chemical	

Engineering	self	organizing	nano‐systems.	Such	superb	manufacturing	

at	the	atomic	level	could	possibly	enable	facsimiles	of	trabecular	bird	

bones,	ultra	light	structural	members,	as	well	as	“ageless”	materials,	

bereft	of	the	contaminants,	dislocations	and	inhomogeneities	that	

degrade	the	strength	and	usability	of	current	materials.	For	nearly	2	

decades	the	prevalent	opinion	was	that	such	strong	nano,	AKA	

“Molecular	Manufacturing”,	was	not	executable.	Recently	several	groups	

are	making	progress	and	success	is	expected	in	due	course.	IF	this	

“happens”	then	very	localized	manufacturing	is	enabled,	e.g.	“fab	Labs”	

in	the	home,	and	the	demand	for	cargo	air	transport	would	probably	

plummet.	In	the	runup	“free	form	fabrication”	by	various	means	

including	electron	beams	is	increasingly	prevalent	and	increasingly	
13	

termed	the	“Third	Industrial	Revolution”	[The	first	two	were	in	the	19th

and	20th	centuries	respectively].		

		Nano	also	enables	a	plethora	of	sensors/	instruments	for	Integrated	

Vehicle	Health	Management	[IVHM]	and	safety	as	well	as	“situational	

awareness”	writ	large	which	is	enabling	for	the	All	Electron/	photon	

ATC/Nav/Ops	system	mentioned	previously.		CNTs	are	an	interesting	

potential	combination	of	structural	material,	energy	storage	material	

[H2,	Electrical],	sensor	web[s]	and	even	computing	as	well	as	actuation.	

Very	advanced	batteries	enabling	serious	consideration	of	electric	

aircraft	of	various	scales	and	CNT	tethers	for	high	altitude	wind	energy	

harvesting	are	additional	potential	“gifts”	of	Nano,	as	are	ice	and	bug	

phobic	surfaces	for	safety	and	laminar	flow	control	optimization.	

	Energetics	‐	Perhaps	the	poster	child	for	an	Energetics	Revolution	is	

LENR,	Low	Energy	Nuclear	Reactions.	There	are	now	some	20	plus	

years	of	worldwide	experiments,	over	a	hundred	of	such,	producing	

heat	in	excess,	often	far	in	excess,	of	chemical,	and	various	

transmutations,	with	little	worrisome	radiation	and	at	EV	energy	inputs	

not	the	MEV	necessary	to	surmount	the	coulomb	barrier.	There	are	now	

several	theories	for	this	which	indicate	weak	interactions,	not	the	strong	

force,	are	responsible,	and	there	are	now	many	devices	worldwide	

producing	many	watts	to	kilowatts	whose	efficacy	we	are	trying	to	vett.	

If	this	energetics	technology	proves	real	and	scalable	and	safe	then	Aero	

is	changed	MUCH.	We	can	then	enter	into	a	design	space	where	we	have	

never	been	before	–	Energy	Rich.	Measurements	indicate	LENR	is		some	

100	plus	times	chemical	energy	density	with	the	theory	indicating	a	

factor	of	over	1,000,000.	Such	energy	density	with	little	radiation	to	

worry	about	enables	a	Myriad	of	revolutions	in	Aero:	

‐ Energy	focused	far	ahead	of	an	SST	to	reduce	Sonic	Boom	

‐ SSTs	that	have	little	environmental	impact,	ultra	low	fuel	fraction	

and	are,	overall,	Affordable.	

‐ Ability	to	reduce	the	disk	loading,	reduce	propulsor	efficiency	to	

enable	Quiet	VTOL/STOL	operations,	i.e.	in	and	out	of	the	street	in	

front	of	your	house	in	a	“neighborly	fashion”.	Overall	approach	also	
14	

applies	to	reducing	transport	and	SST	noise	–	reduce	loading/	

efficiency	in	favor	of	noise	reduction	as	have	a	surfeit	of	energy.		

‐ For	anything	that	flies,	greatly	reduced	fuel	fraction/	gross	weight,	

therefore	reduced	dry	weight,	huge	range	increases	and	massive	

loiter	improvements	for	climate/	other	“sensor	craft”,	“wholly	

Green”	

‐ Energy	for	direct	control	of	wake	vortices/	vortex	hazard	and	flow	

control	for	bird‐like/	all	weather	flight	as	well	as	superstol	for	

nearly	simultaneous	takeoff	of	several	aircraft	on	the	same	runway,	

increasing	airport	“productivity”.	

		‐			Design	Margins	for	fail‐safe	safety	engineering,	including	engine	

surrounds,	effective	Faraday	cages	for	EMP	protection,	‘chutes	for	large	

aircraft	[or	retro‐rockets]	as	well	as	“crashworthy”	aircraft.	The	many	

safety	issues	associated	with	fuel	explosions/	fires	“go	away”.

		The	estimated	costs	of	energy	produced	for	the	Grid	via	LENR	is	the	

order	of	25%	that	of	coal,	a	VERY	EARLY	DAYS	estimate,	but	indicates	

positive	cost	margins	wrt	petroleum.	

		In	addition,	there	are	emerging	sources	of	biofuels	with	massive	

capacity	and	low	cost	[~	$50/bbl].	These	include	Joule	Biotechnology	

approaches,	Genomic	Cyanobacteria	which	produce,	per	their	assertion,	

some	20,000	gals/	Acre‐year	using	CO2,	waste	water	and	sunlight.	Also,	

Halophytes,	or	salt	plants	[there	are	some	10,000	of	such	extant]	which	

grow	on	wastelands	using	seawater	irrigation.	We	are	running	out	of	

fresh	water	but	some	97%	of	the	water	is	saline	and	some	44%	of	the	

land	mass	is	wastelands.	Seawater	contains	some	80%	of	the	nutrients	

to	grow	plants.	Estimates	indicate	that	just	a	goodly	portion	of	the	

Sahara	is	capable,	via	halophytes	and	seawater	irrigation,	of	producing	

enough	biomass	to	replace	all	the	fossil	carbon	fuels,	producing	the	

petro‐chemical	feedstock	for	the	plastics	and	sufficient	food	to	enable	

release	back	to	direct	human	use	of	some	of	the	68%	of	the	Fresh	water	

now	used	for	Conventional	Agriculture.	Halophytes	grown	on	
15	

wastelands	irrigated	with	seawater	would	“solve”	land,	water,	food,	

energy	and	climate.	

		Both	of	these	advanced	Energetics	options	are	“Green”,	sans	net	CO2	

emissions.	The	Halophyte/	cyanobacteria	sourced	fuels	would	emit	CO2	

when	combusted	but	with,	in	the	case	of	Halophytes,	better	than	a	

closed	CO2	cycle	due	to	root	sequestration	during	growth.		In	the	LENR	

case	there	are	no	CO2	emissions	and	estimates	based	upon	the	

efficiency	of	current	devices,	yet	to	be	validated,	suggest	that	some	1%	

of	the	worlds’	yearly	Nickel	production	could	produce	the	worlds	

energy	requirements.	LENR	produces	heat,	which	could	be	directly	used	

as	a	combustor	replacement	or,	via	such	as	Pyro‐electrics,	T‐PV	or	

sterling	cycles,	produce	electricity	for	propulsion.	In	regard	to	the	other	

major	green	house	efflux	from	aviation,	water,	LENR	emits	none.

Biofuels	do	emit	water	and	therefore	their	use	requires	in	general	flight	

below	the	tropopause	[below	some	27K	ft.]	where	water	efflux	is

cooling	rather	than	“warming”.		

	Synopsis	,	Resulting	Emerging	Technology‐enabled	Aero	Markets	and	

Systems	‐		Given	serious	research,	the		rapidly	evolving	technology	

revolutions	and	the	large	number	of	tech	options	to	achieve	success	the	

following		appear	to		constitute	a	conceptual	laydown	of		the	“Frontiers	

of	the	Responsibly	Imaginable”	in	Aeronautics	going	forward:	

‐ Reduced	long	haul		passenger	traffic	[	due	to	“Tele‐Travel]	

‐ Reduced	long	haul	cargo	traffic	[	due	to	Molecular	Manufacturing	

and	Fab	Labs	in	the	runup]	

‐ An	economical	fail	safe‐safe	totally	robotic	ATC	/Nav/ops	system	[	

Digital	Airspace]	to	enable	UAS	in	controlled	air	space	for	DOD,	DHS	

and	Civilian	use	

‐ Robotic	Delivery	Vehicles	

‐ PAVE	vehicles	to	partially‐to‐?	Replace	Autos	[	~	$1T	world	wide	

Aero	market]	

‐ Greatly	improved	Long	Haul	Transport	Performance	[	via	ideation

and	Mod‐Sim]	

‐ SSTS,	courtesy	of	LENRs	

‐ Ultra‐long	loiter	sensor	craft	for	climate/	other	studies/	uses

‐ Greatly	reduced	Wind	Tunnel	Utilization	[	via	Mod‐Sim‐to‐quantum	

computing]	
16	

			

	Additional	Societal	Changes	Going	Forward	that	will	Impact	

Aeronautics	‐	In	addition	to	the	“Tele‐Everything”	Societal	changes	

noted	herein	there	are	several	other	simultaneous	and	significant,	

mostly	human‐engendered	,Societal	Issues	that	will	impact	the	

aeronautics	industry	going	forward	in	various	ways.	The	climate

positive	feedbacks	are	kicking	in	[methane	hydrates,	fossil	CO2,	

reduced	Ocean	CO2	uptake,	increased	water	vapor,	altered	albedo	etc]	

making	the	IPCC	climate	projections	appear	to	be	conservative.	There	

will	probably	be	increasing	regulations	regarding	emissions	

reductions.	The	massive	debt	issues	worldwide	are	projected	to	

increase	taxes,	inflation	and	interest	rates	before	they	are	resolved.	For	

the	number	of	humans	extant	and	the	way	we	are	currently	living	we	

are	apparently	short	some	40%	of	a	planet,	many	portions	of	the

Ecosystem	are	“crashing”.	As	the	Asians,	at	some	9%	growth	rates	,	

attempt	to	attain	western	living	standards	we	are	projected	to	be	short	

some	3	planets.	The	ecosystem	strictures	will	probably	replace	the	

economic	growth	mantra	with	sustainability.	Also,	the	increasingly	

pervasive	and	capable	automatics	and	robotics	are	replacing	humans	

in	the	workplace	at	increasing	rates.	Suggest	perusal	of	the	Martin	

Ford	book	“The	Lights	in	the	Tunnel”.	And,	humans	are	becoming	

cyborgs,	including	development	of	“brain	chips”.	The	effects	of	much	of	

these	pressures/	changes	will	be	to	reduce	standards	of	living	and	

foster	ever	greater	use	of	“virtual”/	tele‐living	writ	large.		The	“Virtual	

Age”	is	slated	to	follow	the	IT	Age	and	we	are	rapidly	enabling	such.	

Emerging	Aero	Configurational	“Big	Ideas”	

		Long	haul	transports	have,	since	the	50’s,	followed	an	evolutionary	

path	dedicated	to	variants	of	the	707	theme.		Various	engine	

arrangements	were	realized	but	basically	a	tubular	fuselage	and	single	

cantilever	wing.	The	Aero	performance	for	such	machines	has	

improved	little	over	that	time	frame.	One	method	of	intuiting	potential	

alternative	configurations	is	to	list	and	obviate	the	common	

configurational	assumptions.	These	include	such	as	functional	

separation	of	airframe	and	propulsion,	Aerodynamic	controls,	
17	

horizontal	symmetry,	high	lift/	takeoff	capacity	built	into	the	aircraft,	

Etc......Possible	obviations	include	multiple	bodies,	truss	bracing,		

Multi‐stage	aircraft,	Ski	Jumps	for	takeoff,	Thrust	vectoring	for	control,	

yawed	wing[s],	Etc........Over	the	years	a	Plethora	of	configurational	

“deviations”	from	the	“707”	norm	have	been	studied	to	various	levels/	

degrees.	As	an	example	transonic	“Bi‐Plane”	studies	have	indicated	,	

using	updated	technologies,	a	60%	reduction	in	wing	weight	and	30%	

increase	in	L/D	along	with	reduced	vortex	hazard.	Thus	far	this

configuration	has	not	been	taken	up.	Ring	wings	were	also	studied	to	

some	degree	and	also	not	taken	up.	Of	the	vast	panoply	of	previous	

configurational	concepts,	the	present	report	considers	some	updates	to	

what	may	be	considered	the	concepts	that	define	various	“Frontiers”,		

hence	the	term	“Big	Ideas”.		

		Refs.	1‐58	and	refs.	therein	provide	a	robust	sampling	of	the	extant	

Aero	Configurational	Advanced	Concepts	literature.	What	is	interesting	

and	concerning	is	this	literature	is	not	far	greater	and	richer	and	

adopted/	applied.	The	NASA	Institute	for	Advanced	Concepts	for	many	

years	solicited	proposals	for	Advanced	Configuration	Aero	concepts	

and	received	only	a	small	number.	In	recent	years	NASA	engaged	

industry	in	ideation	of	exceedingly	advanced	aircraft,	the	“N+3

Studies”.	These	produced	concepts	with	astoundingly	large	projected/	

estimated	reductions	in	fuel	burn	but	the	major	technology	

contributions	were	primarily	in	propulsion	and	structures/	materials	

vice	Aero.	Boeing	did	proffer	a	version	of	the	Truss‐braced	wing	and	

MIT	advanced	a	unique	“double‐bubble”	lift	carrying	fuselage	with	

serious	propulsion	integration.	These	efforts	provide	an	“existence	

proof”	that	configuration	Aero	still	has	considerable	room	for	

improvement	and	belies	the	enduring,	since	the	50’s,	reliance	on	and	

utilization	of	the	B‐47/	707	configuration	Genre.	What	is	perplexing	is	

that	an	advanced	configuration,	the	BWB,	which	proffers	considerable	

improvements	in	performance,	has	enjoyed	serious	study	now	for	over	

2	decades	worldwide,	has	the	B‐2	as	a	flying	exemplar,	and	yet		has	not	

been	taken	up/	deployed.		As	the	various	Aeronautical	issues/	

problems	discussed	previously	herein	become	yet	more	acute,	this	

situation	should	change.	Historically	such	Aero	configurational

innovation	in	the	U.S.	was	fostered/	enabled	by	pioneering	Military	

advances.	With	the	advent	of	increasingly	serious	Aero	Competition,	

from	Airbus,	the	Brazilians	and	the	Chinese	among	others	

breakthroughs	in	configuration	Aero	could	well	occur	outside	the	U.S.		
18	

		Truss	Braced	Wing	Et	Al	‐	Pfenninger	has	long	advocated	strut/truss	

bracing	to	improve	the	performance	of	conventional	transports.		The	

resulting	(bending,	torsion)	structural	benefits	allow	reduced	wing	

weight,	thickness	and	sweep,	resulting	in	a	tremendously	enhanced	and	

easily	maintained	(reduced	sensitivity	to	roughness/insect	remains/ice	

clouds,	reduced	cross	flow)	extent	of	natural‐to‐easily	forced	low	drag	

laminar	flow,	along	with	increased	span.		The	latter	allowed	a	reduction	

in	wing	chord,	further	enhancing	the	extent	of	laminar	flow,	as	well	as	

enhanced	takeoff	and	climb	performance	and	reduced	vortex	hazard.		

Plenninger’s	designs	for	such	aircraft	yielded	L/D	values	in	the	40’s,	

over	twice	current	levels	with	one	of	his	studies	which	included	a	

laminar	fuselage	yielding	a	machine	with	L/D	=	100,	700	Pax	and		

200,000	Km	range..		The	concept	was	not,	however,	adopted	primarily	

because	the	extensive	wing	span	did	not	fit	the	FAA	“80	meter	box”	for	

airport	gate	compatibility	and	disbelief	that	a	transonic	strut/truss	

braced	wing	could	be	designed	with	acceptable	shock	drag	(and	obtain	

laminar	flow	on	the	strut/truss).		Obviously	strut‐bracing	is	routinely	

employed	on	low(er)	speed	aircraft.			The	latter	objection	is	probably	

not	valid	in	light	of	today’s	CFD	capabilities.	In	general,	we	build	what	

we	can	compute	and	we	have	been	too	long	constrained	in	aircraft	

design	to	linear	theory	and	consequent	“linear	thinking.”		Indeed,	lack	of	

adequate/believable	“first	principles”	estimation	methods	for	not	only	

performance	but	cost(s),	maintenance/operability,	etc.	are	a	major	

reason	why	work	on	advanced	aero	concepts	has	lagged.		Our	current	

systems	methodologies	are	essentially	extrapolation	and	interpolation	

procedures	based	upon,	and	therefore	largely	restricted	to,	empirical	

data	for/from	the	current	paradigms.	As	discussed,	the	improved

computing	machine	capabilities/	mod‐sim	developments	are	changing	

such	considerations/	judgements	in	real	time.	

	 The	span	of	a	truss‐braced	configuration	can	probably	be	doubled	

and	a	mid	span	hinge	[already	studied	in	industry]	utilized	to	conform	

to	the	80	meter	gate	requirement.		Doubling	span	would	halve	Reynolds	

Number	on	the	wing	and	reduce	drag	Due	To	Lift	the	order	of	75%.	

Combining	this	DDL	reduction	with	the	extensive	wing	Laminar	Flow	

results	in	most	of	the	remaining	vehicle	drag	being	fuselage	friction	

drag.		Such	drag	can	be	addressed	in	several	ways.	The	most	dramatic	is	

to	apply	boundary	layer	relaminarization	just	downstream	of	the
19	

cockpit	/forward	door.	The	aircraft	nose	region	with	the	radome,	

probes,	windshield,	wipers	etc.	will	be	turbulent,	therefore	need	to	

ingest/	take	aboard	some	150%	plus	[to	entrain	the	turbulent	

“Superlayer”]	of	the	local	fuselage	turbulent	boundary	layer	and	re‐

establish	laminar	flow.	The	increasing	use	of	personal	view	screens	vice	

windows	greatly	eases	the	task	of	maintaining	laminar	flow	

downstream.	The	air	taken	aboard	can	be	slot	injected	into	the	

turbulent	wing‐fuselage	turbulent	flow	wedge	to	accrue	local	skin	

friction	reduction.	

		The	engines	can	be	moved	to	the	rear	of	the	fuselage,	surrounded	by	a	

Goldschmied	shroud.	This	would	enable	several	interesting/	useful	

functionalities.	The	engines	could	be	thrust‐vectored,	obviating	the	

weight/	drag	of	the	empannage.	The	shroud	provides	copious	volume	

for	acoustic	treatment[s].	The	engines	ingest	the	fuselage	boundary	

layer	accruing	a	sizable	propulsion	improvement.	Then	there	is	the	oft‐

mentioned	but	still	under	study	“Goldschmied	Effect”	that	purportedly	

could	cancel	a	sizable	portion	of	the	fuselage	friction	drag.	The	thought	

is	that	possibly/	TBD,	putting	“sinks	inside	the	body”	using	the	cowl	

could	convert	the	back	of	the	cowl	into	a	stagnation	region,	thereby	

producing	what	Goldschmied	called	favorable	interaction	“Static

Pressure	Thrust”.		

		For	long	haul	transports	the	weight	of	the	gear	is	the	order	of	half	the	

fuselage	weight.	The	gear	weight	could	be	reduced	in	several	ways.	One	

is	to	utilize	‘chutes	instead	of	super	heavy	brakes	for	refused	takeoff.	

Another	is	to	utilize	wholly	automatic	landings	with	the	controls	slaved	

to	the	altitude/	ground	proximity	and	decent	rate	to	take	out	the	impact	

loading.		Yet	another	is	to	employ	imbedded	hydraulics	in	the	gear	

structure	to	provide	rigidity	only	when	needed	vice	carrying	the	weight	

throughout	the	mission.	All	of	these	benefits	greatly	reduce	vehicle	

weight	overall,	which	along	with	clever	vortex	flow	control	can	reduce	

wake	vortex	hazard.	

		The	conceptual	advanced	engine	technologies	mentioned	herein	could	

perhaps	improve	propulsion	efficiency	the	order	of	50%	[including	the	

aft	engine	viscous	flow	ingestion].	Advanced	materials	on‐the‐way	to	

eventual	development/	invention	of	structural	Nano	Tubes,	along	with	

the	possibility	of	using	inflatable	inboard	wing	sections	to	enable	
20	

further	sweep	reductions	provide	weight	reductions,	including	the	truss	

benefits	on	wing	weight,	in	the	range	of	[	GROSS		ESTIMATES]	some	

30%	to	double	that.	The	computed	L/D	for	these	configurations	are	in	

excess	of	40	to	much	higher.	The	resultant	fuel	burn	reductions	are	,	

without	going	to	fuselage	laminarization	but	using	riblets	for	turbulent	

viscous	drag	reduction,	in	excess	of	70%	.........	Obviously	as	LENR	

energetics	is	developed,	if	it	can	be	developed	at	the	requisite	power	

levels,	the	fuel	fraction	becomes	seriously	small	and	gross	weight/	

vortex	hazard	reduce	further.	

		It	should	be	noted	that	we	have	no	detailed	studies	of	truss	braced	

wing	truss	optimization.	The	studies	thus	far	have	been	at	the	systems	

not	the	detailed	design	level.	We	have	never	been	here	before.	Obvious	

options	include	pre‐stressing,	hydraulic	dynamic	internal	

pressurization,	laminar	elements,	arching,	“Y”	intersections	with	the	

wing	to	avoid	supercritical	flow	regions,	optimizing	the	overall	number,	

nature,	positioning	of	the	elements,	ETC.	The	truss	could	be	carried	out	

beyond	the	mid	span/	wing	hinge	position,	all	of	these	options	and	far	

more	are	forward	work.			

	 	

Blended‐Wing	Body	‐	At	some	level	the	major	players	(U.S.,	Europeans,	

Russians)	are	studying	the	technology	for	a	jumbo	aircraft	in	the	800+	

PAX	range	which	is,	“different”‐‐some	variant	of	the	spanloader	or	

“blended	wing	body”	(BWB).	Jumbo	options	aside	from	conventional	

and	BWB	include	multi‐body	and	wing‐in‐ground	(WIG)	effect.		The	

multi‐body	(double	fuselage/	midwing	discussed	herein)	is	a	viable	

candidate	but	the	WIG	is	probably	not.		Study	of	the	extensive	Russian	

work	in	the	WIG	arena	indicates	several	nontrivial	problem	areas	for	

the	WIG	vis‐a‐vis	the	long	haul	transport	mission	‐	operation	near	the	

surface	in	high	density	air	engendering	a	high	drag	level,	structural	and	

propulsive	weight	inefficiencies	associated	with	water	impact	and	

takeoff	thrust	requirements	and	safety	problems	associated	with

operation	at	the	extremely	low	altitudes	required	to	attain	appreciable	

ground	effect	benefits	on	“cruise”	L/D.		

		 The	success	of	a	“deployed	version,”	the	B‐2	bomber,	triggered	

interest,	worldwide,	in	spanloader/	blended	wing‐body	aircraft.		The	

major	performance	benefits	of	such	aircraft	addresses	the	major	issues	

for	jumbo	aircraft‐‐noise	and	vortex	hazard	engendered	by	their	great	
21	

weight.	Obvious	benefits	of	spanloader	aircraft	include	large	increases	

in	L/D	(due	primarily	to	the	demise	of	[	much	of	the]	fuselage	wetted	

area/skin	friction)	and	reduction	in	empty	and	gross	takeoff	weight.		

The	design	approach	“puts	the	lift	where	the	load	is”	for	a	requisite	size	

aircraft	with	a	physical	wing	thickness	sufficient	to	allow	passenger	

seating	within	the	wing.			The	technological	challenges	(as	well	as	the	

opportunities)	of	an	800+	PAX	long	haul	BWB	transport	are	tremendous	

but	at	least	thus	far	evidently	“workable.”		These	challenges	include	

thick	wing	sections	(possibly	with	hybrid	LFC	and	synergistic	

(“Goldschmied”)	propulsion	integration),	non‐circular	pressure	vessels,	

stability	and	control,	emergency	passenger	egress,	airport	compatibility	

and	very	high	Reynolds	number	aerodynamics‐‐both	high	lift	and	cruise.		

The	BWB	design	inherently	contains	a	major	surfeit	of	internal	volume	

and	is	therefore	highly	conducive	to	enhanced	range,	cargo	operation	

and	passenger	comfort.		In	regard	to	the	latter	benefit,	“sleeper”	

versions	of	the	BWB	could	provide	very	interesting	competition	to	SSTs	

for	trans‐Pacific	routes	in	terms	of	enhanced	comfort/lower	price	

versus	shorter	transit	time/cramped	seating	and	higher	price.		The	

USAF	“New	World	Vistas”	study	specifically	called	out	the	BWB	

approach	as	an	excellent	candidate	to	provide	enhanced	“global	reach”	

airlift	capability‐‐in	conjunction	with	precision	(GPS‐guided)	delivery	

pallets	as	an	alternative	to	the	vehicle	design	decrements	and	

vulnerability	of	landing	“in	theater.”		The	large	payload/volume	and	

extraordinary	range	of	BWB	transports	also	provides	capability	for	high	

capacity	paratroop	drops,	cruise	missile	or	UCAV	carriage/launch,	

“AWACS”	missions	and	“aerial	replenishment.”	

Double	Fuselage	‐	Conventionally,	double	fuselage/multi‐body	

aircraft	have	been	employed	to	provide	span‐load	distribution	and	

accrue	the	associated	structural	weight	benefits	(reduced	wing	bending	

moment)	without	going	all	the	way	to	a	“blended	wing	

body”/spanloader	configuration	i.e.,	providing	such	benefits	via	

“conventional”	(e.g.,	“comfortable”)	technology.		Total	aircraft	drag	is	

also	reduced,	primarily	due	to	favorable	effects	on	drag‐due‐to‐lift.	

	 An	advanced	double	fuselage	approach	could	attempt	to	delete	

the	conventional	outer	wing	panels	and	only	retain	a,	largely	

unswept/long	chord,	wing	section	between	the	fuselages.		This	requires	

prodigious	drag‐due‐to‐lift	reduction,	a	requirement	which	can	be	
22	

addressed	via	design	of	the	fuselages	as	wing‐tip	“end	plates”	and	the	

individual	fuselage	empennage	as	“winglets,”	i.e.,	the	tails	become	

thrusting	surfaces	in	the	presence	of	the	wing	vorticity	wrapping	

around	the	fuselage(s).	

	 For	this	case,	the	“midwing”	can	become	the	site	of	the	gear	(to	

allow	use	of	conventional	runways),	with	engines	“buried”	at	the	rear	of	

the	fuselages	to	accrue	the	benefits	of	“boundary	layer	ingestion”	and	

drag‐due‐to‐lift	reduction,	with	extensive	(natural/	suction)	laminar	

flow	enabled	by	the	largely	unswept	“midwing.”	Spanwise	and	localized	

ahead	of	the	neutral	curve	heating	strips	in	the	wing	leading	edge	region	

would	enable,	from	theory	and	experiment,	longer	regions	of	laminar	

flow.	The	approach	essentially	converts	the	wing	surface	downstream	of	

the	neutral	curve	into	a	“cooled	region”	as	far	as	the	incoming

[upstream	heated]	flow	is	concerned	and	for	these	speeds,	in	unswept	

flows,	cooling	is	stabilizing.	A	major	payoff	would	accrue	from	making	

the	fuselages	detachable/interchangeable	to	provide	a	civilian	“sky‐

train”	with	enhanced	productivity.		The	midwing	portion	which	does	all	

the	“flying”	could	be	in	the	air	nearly	“around	the	clock”	with

interchangeable	freighter	and/or	passenger	modules,	thereby	nearly	

doubling	the	productivity/	duty	cycle	and	“return	on	investment.”		Such	

an	approach	would	allow	a	restructuring	of	the	airline	capital	

investment,	with	the	airlines	“owning”	their	fuselages	and	leasing	the	

“midwing”	from	a	“rent‐a‐wing”	company.			Obviously,	military	versions	

could	have	cargo,	troop,	and	refueling	fuselages‐‐providing	a	quantum	

jump	in	military	flexibility	and	productivity.	

PERSONAL	AIRCRAFT‐	The	“Converticar	‐	The	developed	nations	

entered	the	1900’s	with	a	transportation	system	(for	people)	centered	

upon	the	horse,	the	railroad	and	the	steamship,	with	associated	travel	

times	the	order	of	hours‐to‐days/weeks,	depending	upon	distance.	The	

automobile	has	long	supplanted	the	horse	and	the	fixed	wing	aircraft	

has	nearly	driven	the	railroads	and	steamship	companies	from	the	long	

haul	passenger	business.		Travel	times	have	shrunk	to	minutes‐to‐hours.	

These	newer	approaches	have	also	had	a	profound	influence	upon	the	

structure	of	modern	societies.		In	the	U.S.,	cities	have	expanded	out	of	

18th	century	seaports	and	19th	century	railheads,	where	much	of	the	

developed	region	was	by	necessity	within	walking	distance	of	the	

transportation	terminals,	into	tremendous	automobile‐enabled	suburbs	
23	

with	attendant	reductions	in	crowding/increased	opportunity	for

individual	home	ownership	etc.	

	 This	section	considers	future	possibilities/options	for	the		non‐

transoceanic	transportation	spectrum,		with	emphasis	upon	the	range	

from	10’s	to	100’s	of	miles.		The	current	dominant	transportation	mode	

for	this	mission	is	the	automobile,	which,	possibly	more	than	any	other	

single	technical	achievement,	has	enabled	the	current	life	style	enjoyed	

by	the	developed	nations.		In	this	process,	the	auto	has	created	massive	

safety	problems	(order	of	40,000	deaths/year	in	the	U.S.	due	to	highway	

accidents‐‐which	is	the	order	of	the	U.S.	casualty	count	for	the	entire	

Vietnam	War)	and	has	been	responsible	for	the	expenditure	of	truly	

prodigious	sums	on	roads,	bridges,	pollution‐induced	health	and

material	degradation	remediation	and	the	legal	system.		The	current	

status	of	the	auto	infrastructure	is	that	we	continue	to	clear	and	pave	

more	of	the	watershed,	contributing	to	air	pollution,	flooding,

desiccation,	the	formation	of	heat	islands	and	wildlife	habitat

degradation.		Also,	the	average	trip	time	is	increasing	due	to	suburban	

expansion	and	increased	congestion,	causing	non‐trivial	changes	in	

family	life	as	travelers	attempt	to	utilize	non‐traditional	time	slots,	or	

suffer	long/nonproductive	commutes.	

	 Society	cannot,	easily	or	otherwise,	continue	to	bear	the	costs	

imposed	by	almost	sole	reliance	upon	the	automobile	for	short‐to‐

intermediate	passenger	transport,	alternatives	are	necessary	for	the	

future‐‐both	for	the	developed	societies	and	those	that	desire	to/are	

developing.		Probably	the	most	commonly	advocated	alternatives	

involve	some	form	of	mass	transit,	which	have,	along	with	tremendous	

capital	costs,	several	other	drawbacks	such	as	passenger	wait	time,	

weather	exposure	and	lack	of	privacy,	security,	pride	of	ownership	and	

personal	stowage.		Additional	drawbacks	are	the	fact	that	they	are	not	

portal‐to‐portal	and	there	is	no	guarantee	of	having	a	seat,	as	well	as	an	

inherent	assumption	and	economic	realism	regarding	required	

population	density/concentration.		Undoubtedly,	the	future	mix	of	

short‐to‐intermediate	transport	systems	will	include	both	mass	transit	

and	automobiles	of	some	variety,	probably	operated	on	“intelligent”	

highways	to	improve	safety	and	throughput/trip	time.			

	 There	is,	however,	both	a	need	and	an	emerging	opportunity	to	

include	in	the	transportation	mix	a	personal	air	vehicle	which	would	

provide,	percentage‐wise,	the	same	increase	in	speed	(compared	to	the	

auto	in	traffic),	as	the	auto	provided	over	the	horse.		Personal	air	
24	

transportation	usable	by	“everyone”	is	both	revolutionary	and	the	next	

logical	step	in	the	development	of	human	infrastructure	and	corporal	

communication.		The	increased	speed	and	potential	safety	

improvements	of	such	a	capability,	along	with	the	greatly	reduced	

capital	requirements	in	terms	of	highways/bridges,	etc.,	should	allow	

significant	increases	in	the	quality	of	life	as	well	as	reduced	state	and	

national	public	works	budgets.		Specific	benefits	include	distribution	of	

the	population	over	a	much	larger	area	allowing	a	more	peaceful/less	

damaging	co‐existence	of	man	and	nature,	along	with	improved	

transportation	safety.		The	“vision”	is	of	multilevel	highways	in	the	sky,	

controlled	and	monitored	by	inexpensive	and	reliable	electronics	and	

communications	as	opposed	to	narrow,	single	level,	exceedingly	

expensive	“ribbons	of	concrete.”		Such	air	systems/vehicles	could	also	

obviously	be	used	for	long(er)	haul,	as	are	automobiles	today,	e.g.,	travel	

of	500	miles	or	less	is	currently	usually	accomplished	via	auto.		With	a	

(faster)	personal	air	vehicle	this	distance	could	be	the	order	of	1500	

miles	or	more.		This	in	turn	would	have	a	major	impact	on	domestic	

scheduled	commercial	air	travel,	90	percent	of	which	is	over	distances	

of	1500	miles	or	less.	The	various	wait	times	associated	with	

commercial	air	travel,	along	with	the	inefficiencies	in	terms	of	transit	

time	of	the	hub	and	spoke	system	mitigate	in	favor	of	reduced	overall	

trip	time	for	slower,	but	more	direct,	travel	via	personal	aircraft	

(compared	to	the	“faster”	commercial	jet).		Various	options	exist	for	

personal	aircraft	systems.		Certain	requirements/desirements	are	

common	to	any	personal	transportation	vehicle/system.		These	include,	

besides	affordability,	short	transit	time/high	speed,	direct	portal‐to‐

portal,	privacy	and	security,	constant	availability,	personal	stowage	and	

a	suitability	for	use	by	the	“non‐pilot.”		The	latter	necessitates	from	the	

outset	that	an	obvious	(and	probably	attainable)	goal	should	be	an	

automatic	personal	air	transport	system,	automatic	with	respect	to	

navigation,	air	traffic	control	and	operation.		The	technology	to	

accomplish	this	is	either	currently	employed	by/for	the	long	haul	air	

transport	application,	or	in	the	research/application	pipeline,	thanks	to	

the	IT	revolution	and	includes	GPS,	communication	satellites	and	the	

military	investments	in	RPV’s,	AAV’s,	UAV’s,	UTA’s,	UCAV’s,	MAV’s,	UAS	

etc.		Such	automatic	operation	could	provide	vastly	improved	safety,	as	

the	preponderance	(70	percent	to	80	percent)	of	air	transport	accidents	

have	historically	been	due	to	“human	error.”		In	addition,	it	makes	

personal	air	vehicle	transportation	available	to	the	general	public,	as	
25	

opposed	to	the	few	who	have	the	opportunity,	wealth,	and	physical	

characteristics/health	to	become	pilots,	as	well	as	reducing	the	unit	cost	

by	an	order	of	magnitude	or	more	due	to	the	concomitant	vast	increases	

in	production	rate/market.	

	 To	be	competitive	with	the	automobile	a	personal	VTOL‐

converticar		[	‘PAVE”]	should	have	an	acquisition	cost	in	the	vicinity	of	a	

quality	automobile.		Although	in	terms	of	the	current	main	line

helicopter	industry,	this	is	a	ridiculous	target,	the	advantages	of	a	

production	run	of	millions	instead	of	hundreds,	along	with	the	current	

offerings	of	a	single	seat	helo	for	$30K	and	a	two‐place	“gyroplane”	for	

$20K,	all	at	small	production	runs	makes	the	outlook	to	achieve	such	a	

goal	possible	if	not	probable.	All‐weather	operation	is	also	a	

requirement,	the	same	all‐weather	capability	one	now	has	in	an	

automobile,	which	is	by	no	means	absolute.		Extremely	heavy	rain,	

extreme	winds,	ice	and	snow	will	all	either	slow	or	stop	the	auto,	and	

similar	restrictions	will	probably	hold	for	the	personal	PAVE	vehicle.		

Obviously	the	evolving	“detect	and	avoid”	technology	could	be	utilized	

(either	on	or	off	board)	to	increase	safety	vis‐a‐vis	extreme	weather.	

	 Over	the	years,	particularly	since	the	1930’s,	there	have	been

suggestions,	and	in	some	cases	strident	calls,	for	the	development	and	

mass	marketing	of	personal	aircraft.		Although	“general	aviation”	has	

made	considerable	advances,	the	“aircraft	for	the	masses”	never	really	

caught	on	for	a	variety	of	reasons,	mainly	involving	COST,	lack	of	

requisite	technology	readiness	and	an	absolute	requirement	that	the	

“operator”	be	a	“pilot,”	e.g.,	non‐automatic	operation.		History	is	replete	

with	examples	of	concepts	which	are	good	ideas	and	which	keep	

resurfacing	until	the	technology	base	or	market	is	ready.			Since	the	last	

personal	aircraft	campaign	in	the	late	40’s‐50’s,	major	strides	have	

occurred	in	several	enabling	technologies.		These	include	light	weight,	

miniature,	inexpensive	and	tremendously	capable	electronics/	

computing	(e.g.,	the	IT	revolution),	lightweight	composite	materials	

with	“nearly	infinite”	fatigue	life,	computational	fluid	mechanics,	smart‐

to‐brilliant	materials/skins,	flow	control	of	several	types	and	active	

controls/load	alleviation.		Such	advances	significantly	change	the	

personal	aircraft	discussion.	

	 	There	are	several	“systems	level”	issues	and	critical	choices

regarding	the	personal	aircraft	which	serve	as	key	discriminators	in	the	

selection	of	a	particular	personal	aircraft	design.	The	first	such	issue	is	

whether	the	personal	aircraft	(either	“fixed”	or	rotary	wing)	should	be	a	
26	

separate	air	vehicle,	or	a	“converticar,”	i.e.,	a	combination	automobile	

and	air	vehicle	capable	of	economically	performing	both	missions.		

Economics	and	utility	strongly	favor	the	“converticar”	option.		There	are	

numerous	elements	common	to	both	the	air	and	ground	vehicles,	such	

as	passenger	compartments,	engines,	etc.	and	therefore,	since	it	is	

technically	feasible	to	reduce	the	weight	of	an	auto	to	what	is

reasonable	for	an	air	vehicle,	then	a	single	vehicle	should	be	

considerably	more	economical	in	terms	of	initial	cost	and	maintenance	

than	buying	and	maintaining	two	separate	vehicles.		Simplex	estimates	

of	the	flight‐specific	component	weights	indicate	a	value	of	less	than	

1000	[	some	indicate	as	little	as	500	]	pounds,	and	therefore	with	shared	

utilization	of	common	systems,	the	“all‐up”	weight	of	the	converticar	

could	be	in	the	(reasonable)	range	of	3000	pounds	or	less.		From	an	

operational	viewpoint	a	single	vehicle	should	be	much	more	convenient,	

obviating	the	need	for	a	“rent‐a‐car”	in	the	vicinity	of	one’s	destination.		

Once	the	converticar	option	is	selected,	some	decision/recommendation	

has	to	be	made	regarding	the	provision	for	the	“air‐unique”	

components,	particularly	the	lift‐producing	surfaces	which	require,	for	

reasonable	levels	of	drag‐due‐to‐lift,	non‐trivial	span/aspect	ratio.		

Options	include	towed	“trailored”	wings	(utilized	in	early	versions	of	

the	converticar),	fixed	wings	of	inherently	low	aspect	ratio	for	

“roadability,”	airport	“rent‐a‐wing”	concessions	where	the	wings	are	

attached	prior	to,	and	removed	at	the	conclusion	of,	flight,	and	

telescoping/folding	wings.		The	present	author	favors	the	

telescoping/folding	option	as	offering	the	best	compromise	between	

convenience	and	performance.	

	 The	next	critical	choice	is	between	conventional/”fixed	wing”	

operation	and	a	rotary	wing	device.		An	essential	difference	is	that	the	

fixed	wing	machine/operation	generally	requires	an	airport	except	for	

powered	lift	approaches	of	various	flavors.		There	are	many	thousands	

of	GA	airports	and	one	would	have	to	begin	and	end	the	air	portion	of	

the	trip	at	one	of	these.		In	the	opinion	of	the	present	author,	this	is	

simply	too	restrictive	and	contravenes	several	of	the	fundamental	

purposes	of	the	personal	air	vehicle	such	as	independence	of/reduced	

requirement	for	large	civil	works,	portal‐to‐portal	transportation,	and	

access	to	remote	sites	(remote	from	roads,	etc.).			

	 The	Super	STOL	option	would	allow	development/usage	of	

currently	undeveloped	nations/regions	at	a	fraction	of	the	cost	of	the	

roads/bridges,	etc.	usually	required	for	such	development,	and	at	much	
27	

less	disruption	to	the	environment.		The	estimated	“off‐shore”	market	

for	such	a	device	is	the	order	of	$.5T/year	with	an	eventual	domestic	

(U.S.)	market	of	the	same	order.	 Another	major	option	involves	the	

extent	to	which	the	operation	in	the	air	mode	should	be	automatic	as	

opposed	to	pilot/human	derived.		While	sport	models	could	be	

somewhat	human‐controlled	(within	the	confines	of	the	ATC/safety	

regulations)	the	optimal	solution	is	clear.		The	portion	of	the	population	

physiologically	capable	of	becoming	pilots	is	not	large	and	there	is	

considerable	cost	and	time	involved	in	doing	so,	most	accidents	are	due	

to	pilot	error,	and	the	ATC	system	requires,	for	the	large	numbers	

ultimately	envisaged,	automatic	operation.		Therefore,	a	user‐orientated	

personal	air	capability	should,	ultimately,	be	automatic	in	operation	as	

well	as	navigation	and	ATC,	as	already	suggested	herein.		To	avoid	the	

“swarm”	problem	the	vehicle	would	probably	be	constrained	to	operate	

in	the	ground	vehicle	mode	in	currently	congested	areas	and	only	

allowed	to	go	airborne/automatic	in	low(er)	population	density	areas	

unless	are	“Over‐Flying”.		Eventually	such	a	vehicle	could	change	

current	land	use	patterns	and	allow	reduced	population	density,	with	an	

effect	on	the	current	built‐up	suburbs	similar	to	that	of	the	automobile	

upon	the	central	cities	which,	at	least	in	the	U.S.,	were	largely	bulldozed	

in	the	50’s	to	80’s	following	the	auto‐enabled	population	exodus.	

	 Such	an	“automatic”	super	STOL	machine	would	also	provide,	in	

an	emerging	world	of	IT‐enabled	increasingly	prevalent	tele‐commuting	

and	“electronic	cottages,”	affordable/robotic	delivery	of	requisite	food	

supplies	for	the	carbon‐based	inhabitants	as	well	as	goods	ordered	on	

the	“net”/shopping	channels.	

	 Similarities	between	the	horse‐to‐auto	transition	and	potential	

auto‐to‐	superSTOL	converticar	transition	include	occurrence	in	the	

early	part	of	the	century	(~	100	years	apart),	both	provoke/enable	

major	changes	in	land	use/ecology,	lead	to	atrophy	of	concentrated	

population	centers,	revolutionize	the	Nation’s	economy/builds	upon	

Nation’s	technological	strengths,	and	have	an	equivalent	percentage	

increase	in	speed	and	personal	action	radius/elbow	room/freedom	of	

action/privacy.		Differences	between	the	two	are	favorable	to	the	

converticar,	which	should	enhance	safety	and	for	which	the	

infrastructure	is	largely	in	place.		We	do	not	have	to	clear	and	pave	the	

watershed	at	prodigious	cost	(as	required	by	the	auto).		The	safety	issue	

for	the	converticar	can	be	approached	via	automatic	operation	and	a	
28	

combination	of	vehicle	parachutes	and	energy	absorbing/crash	worthy	

structural/material	design.	

	 It	is	not	clear	whether	such	a	vehicle	would	make	“sense,”	

economically,	technically	and	society‐wise	for	those	areas,	such	as	parts	

of	Europe,	which	are	densely	populated,	and	for	that	portion	of	the	

human	race	who	prefer	to	live	in	crowded	conditions.		The	IT	Tele‐

Everything	revolution	appears	to	be	removing	much	of	the	economic	

rationale	for	such	population	concentration.	Particularly	enticing	

Converticar	markets	include	places	with	few	intercity	roads	such	as	

Island	Nations	[Indonesia,	Malaysia],	Siberia,	Northern	Canada,	Parts	of	

Africa	and	Alaska	etc.	These	machines	will	and	in	fact	ARE	being	

developed	because	the	technologies	are	now	“ready”,	we	can	now	“do	

this”,	for	cost	avoidance	in	terms	of	infrastructure,	because	the	“tele‐

everything	emerging	lifestyle	requires	such	connectivity	[	e.g.	rapid,	

long	distance	robotic	package	delivery],	the	carnage	on	the	roadways	

and	increasing	auto	trip	times	and	aggravation	and	the	HUGE	markets,	

extremely	interesting	“Business	Cases”.	Congress	in	the	U.S.	has	edicted	

access	into	the	NAS	for	UAS.	PAVE	vehicles	are	simply	UAS	carrying	

PAX.	One	especially	interesting	SuperSTOL	Pave	vehicle	approach	is	a	

channel	wing	with	circulation	control.		

		Pfenninger	Extreme	Arrow	SST	‐	Thus	far	SST’s	have	not	been	

particularly	successful,	either	conceptually	or	in	actual	realizations.	The	

Concord	was	a	technological	marvel	for	its’	time	but	not	commercially	

successful.	Similar	remarks	hold	for	the	TU‐144.	The	basic	SST	issues	

are	straight	forward,	the	many	and	various	Aeronautical	Problems	

discussed	early	on	in	this	report	hold,	but	extended	and	confounded	by	

the	addition	of	serious	wave	drag	,	higher	fuel	fractions,	higher	

temperatures,	and		greater	weights,	all	driving	up	vehicle	cost.	Then	

there	are	the	high	altitude	Ozone/	emissions	problems,	far	more

incident	radiation,	and	the	sonic	boom,	the	latter	causing	anti‐SST	

legislation.	The	sonic	boom	affects	both	people	and	things.	There	has	

been	some	success	in	reducing	the	“N‐wave”	peaks	that	affect	people	

but	reducing	the	low	frequency	“rumble”	that	affects	buildings	etc.	is	a	

much	more	difficult	task.	Lastly,	there	is	the	jet	takeoff	noise	from	the	

engines	designed	for	propulsion	at	supersonic	speeds.		Taken	together	

the	various,	in	some	instances	rather	extensive	studies	over	the	years	

since	Concord	of	SST	potential	viability,	especially	economic	viability,	
29	

have	not	been	optimistic.	There	are	concentrated	studies	ongoing	of	SST	

Business	jets	as	such	smaller	vehicles	both	reduce	the	massive	

investment	level	required	to	field	such	machines	and	also	reduce	the	

sonic	boom,	which	is	first	order	dependant	upon	weight.	

		Advanced	Configuration	SSTs	come	in	five	major	categories,	unswept	,	

thin	natural	laminar	flow	wings,	parasol	wing	favorable	interference,	

multi	stage	aircraft,	yawed	wings	and	the	Pfenninger	extreme	arrow		

strut	braced	wing.	The	multi‐stage	approach	usually	involves	a	stage	

which	includes	the	capability	to	get	off	the	ground	with	acceptable	

noise/	high	lift	etc,	and	then	separates/	returns	to	the	airfield.	The	

portion	of	the	aircraft	that	lands	at	the	end	of	the	flight	weighs	far	less,	

allowing	carriage	of	lighter	weight	gear	and	high	lift	systems	etc...	In‐

Flight	refueling	is	another	multi‐stage	aircraft	option.	The	yawed	wing	

approach	uniquely	provides	a	low	supersonic	Mach	number	option	that	

is	nearly	“boomless”	and	extremely	efficient.		Of	these	the	Pfenninger	

extreme	arrow	strut	braced	wing	appears	to	have	the	greatest	SST	

potential,	essentially	doubling	the	Concord	L/D	of	7.3ish.	The	best	NASA	

did	in	the	HSCT/HSR	program	of	the	late	90’s	was	an	L/D	in	the	range	of	

9.5.	The	Pfenninger	designs	proffer	values	in	the	range	of	14	to	16	plus.	

The	extreme	arrow	wing	minimizes	wave	drag	due	to	lift	and	wing

wetted	area	as	well	as	providing	a	credible	span	for	vortex	drag	

minimization.	The	short	wing	chord	aids	suction	laminar	flow	control.	

There	are	mid‐wing	fuel	canisters	for	favorable	wave	interaction	and	

load	alleviation	with	the	possibility	of	natural	laminar	flow	on	the	

forward	regions	of	the	fuel	cannisters	and	the	fuselage.	Several	

approaches	utilized	to	optimize	the	truss	braced	CTOL	design	can	also	

be	applied	to	this	SST	including	gear	weight	reductions	via	automatic	

landings	and	‘chutes	for	refused	takeoff.	This	is	particularly	important	

in	the	SST	case	as	the	gear	weight	is	the	order	of	the	fuselage	weight.	In	

addition,	C‐Wing	tips	would	reduce	DDL.	The	serious	takeoff	jet		noise	

issue	can	be	addressed	via	an	essentially	new	approach	–	disabling/	

reducing	the	causative	turbulence	dynamics	vice	reducing	the	jet	

velocity	via	entrainment	using	heavy	“Mixer‐Ejectors”.	Experiments	and	

some	theory	indicates	that	the	injection	of	liquid	water	jets,	suitably	

tailored	for	effectiveness	and	minimal	water	mass	flow	can	place	water	

droplets	in	the	mixing	region	of	the	external	jet		which	reduce

turbulence	intensity	and	noise.	The	water	injection	produces	additional	

thrust	vice	the	mixer‐ejectors	that	reduce	thrust	and	is	a	way	of	“staging	
30	

the	aircraft”,	the	water	is	utilized	during	takeoff,	does	not	have	to	be	

carried	throughout	the	flight	as	does	the	mixer‐ejector.	

		Having	such	a	high	L/D	provides	the	margins	necessary	to	address	the	

myriad	SST	problems.	As	mentioned	previously	the	“energy‐rich	

conditions	enabled	by	LENR,	if/as	it	becomes	viable	could,	via	energy	

focusing	well	forward,	greatly	reduce	sonic	boom,	as	well	as,	obviously	

the	fuel	fraction/	attendant	gross	weight,	which	in	turn	further	reduces	

sonic	boom.	

		Probably	“next‐in‐line”	in	terms	of	efficient	SST	configuration	

approaches	would	be	the	oblique/	yawed	wing	and		recent	work	on	a	

Bi‐Directional	Flying	wing	concept	and	the	NASA	N+3	SST	studies.	The	

former	is	due	to	R.T.	Jones	and	is	well	discussed	in	the	literature.	The	Bi‐

Directional	approach	is	circa	2011	and	involves	a	design	based	upon	90	

degree	rotation	of	the	configuration	for	supersonic	vice	subsonic	flight.	

The	design	thereby	provides	major	alterations	in	aspect	ratio	for	each	

speed	range,	enabling	true	bi‐modal	performance	with	excellent	aero	

performance	for	both	supersonic	over	water	and	subsonic	over	land.	

The	overall	approach	is	similar	in	philosophy	to	the	variable	sweep	and		

yawed		designs,	but	executed	in	a	wholly	novel	fashion,	with	efficacy	

TBD.	Such	bi‐modal	aero	performance	improves	the	overall	

performance	for	the	mission	and	reduces	required	fuel	fraction.		

Emerging	Enabling	Aeronautical	Technological	Approaches	

		As	discussed	in	an	earlier	section	of	the	present	report,	Society	is	

currently	undergoing	a	combined,	simultaneous	set	of	technology

revolutions	–	IT,	Bio,	Nano,	Energetics,	Quantum.	These	are	all	occurring	

at	the	frontiers	of	the	small	and	are	often	in	a	synergistic	“feeding	

Frenzy”.	This	section	of	the	report	addresses	the	opportunities	these	

tech	revolutions,	and	some	associated	creative	thinking,	can	engender	

for	several	of	the	fundamental	Aeronautical	Technology	Arenas	–

Aero/Propulsion	interaction,		Flow	Control,	Wave	Drag	Reduction	and	

Drag	due	to	Lift	reduction.	Also	included	under	the	general	category	of	

emerging	Aero	technologies	are	the	breakthrough	propulsion/	

energetics	opportunities.	The	possibilities	associated	with	and	the	

subject	of	LENR	were	previously	discussed	herein.		Then	there	are	the	

approaches,	under	study	at	various	levels	but	not	yet	seriously	applied,	
31	

to	reinvent	gas	turbine	engines.	These	approaches	include	serious	

regeneration,	fostered	by	the	NASA	riblet	technology	to	enable	

reductions	in	heat	exchanger	size/	weight,	wave	rotors,	replacing	the	

last	compressor	and	first	turbine	stages	and	the	combustor	with

dynamic	processes	and	endothermic	fuels/	fuel	cooling.	Overall,

possibilities	for	an	order	of	50%	better	GTE.	

	Aero/Propulsion	Synergies	–	Conventional	design	practice	in	civilian	

aeronautics	is	to	essentially	separate	the	aerodynamics	and	the

propulsion	system.	The	military,	for	over	half	a	century	has	in	many	

cases	utilized	synergistic	combinations	of	Aero	and	Propulsion	to	obtain	

improved	functionality,	often	for	enhanced	high	lift	performance.	Such	

synergistic	combinations	are	equivalent	to	approaching	the	overall	Aero	

design	problem	in	an	open	thermodynamic	system	where	energy	and

mass/	species	are	added	to	the	overall	design	space.	Examples	of	such	

Aero/	propulsive	synergisms	include	the	following:	

‐ Circulation	Control	Wings;	produce	up	to	a	factor	of	4	increase	in	Cl	

[	to	nearly	the	theoretical	4Pi	maximum],	reduced	cost/	part	count	

for	“high	lift”	[	possibly],	improved	control/	maneuverability	

including	provision	of	ride	quality	if	flight	“in	the	weather”	[	below	

the	Tropopause]	is	required	to	address	the	water	emissions	at	

altitude	climate	issue	

‐ Boundary	Layer	Inlet;	Ingesting	lower	momentum	air,	where	the	

Fuselage/other	Aero	skin	friction	has	already	produced	such	

enables	greater	propulsion	efficiency	[	order	of	up	to	10%	to	15%]	

‐ Wing	Tip	Engines;	As	discussed	in	the	subsequent	drag‐due‐to‐left	

reduction	section	placing	the	engines	on	the	wing	tip	can/	has	for	

short	span	wings	reduced	drag‐due‐to‐lift	experimentally	by	up	to	

40%.	The	engine	nacelle	acts	as	an	endplate,	the	engine	energy	and	

mass	addition	change	to	first	order	the	dynamics	of	the	wing	tip	

vorticity	rollup,	also	reduces	wake	vortex	hazard.	Wing	strut	and	

truss	bracing	are	conducive	to	wing	tip	engine	placement.	A	related	

Aero/	Propulsion	interaction	approach	is	wing	tip	injection	using	

engine	bleed	air,	which	also	reduces	wake	vortex	hazard	and	drag‐

due‐to‐lift.	

‐ Thrust	Vectoring;	Placing	the	engines	at	the	rear	of	the	fuselage	and	

utilizing	them	for	Aero	Controls	in	lieu	of	the	weight	and	drag	of	the	

empannage	is	a	major	performance	enhancer.		
32	

‐ Goldschmied	Thrusting	Cowl;		Goldschmieds’	research	indicated/	

he	suggested	that	placing	a	cowl	around	engines	in	the	back,	with	

boundary	layer	inlets,	essentially	puts	potential	flow	“sinks”	inside	

the	body	and	increases	the	pressure	on	the	back	of	the	cowl,	

acquiring	additional	thrust	in	the	process	via	Aero‐Propulsion	

synergy.	Research	is	underway	to	verify,	or	not,	this	assertion.	The	

Submarine	community,	which	utilizes	such	shrouded	pump	jets	

quite	commonly,	have	accrued	some	additional	performance	

benefits,	the	issues	appear	to	be	whether	the	benefits	claimed	by	

Goldschmied,	up	to	some	half	of	the	fuselage	friction	drag,	are

obtainable.	The	boundary	layer	inlet	propulsion	improvements	are	

the	zeroth	order	effect	/	benefit	of	such	a	cowl.	

‐ 	Hybrid	Laminar	Flow	leading	edge	suction	utilized	for	high	lift	

separation	control;	This	is	a	“twofer”,	the	suction	from	the	engine	

used	for	Hybrid	wing		Laminar	flow	at	cruise	for	skin	friction	

reduction	utilized	during	takeoff	for	flow	separation	control/high	

lift.	

				

		Wave	Drag	Reduction	‐	The “usual” (linear theory engendered) 

approaches to wave drag reduction (WDR) include wing sweep, area 

ruling and reduced thickness as well as wing twist/camber/warp. More 

recently Computational Fluid Dynamics (CFD)/nonlinear methods have 

been applied, resulting in further optimization(s). Classical non-linear 

WDR techniques include use of nose spikes (either physical or via 

forward projection of energy, gases, liquids or particulates) to extend 

effective body length – particularly useful on blunt nosed bodies , and 

base blunting which reduces the strength of the base recompression shock 

. 

 All of the WDR methods mentioned thus far involve weakening the 

shock. There is another whole class of approaches which utilize 

favorable shock interference. The fundamental approach is simplex in 

concept – utilize shock waves, via reflection/interaction, to create 

favorable interference either for body thrust or lift, or both. Generally 

volume distributions are utilized to synergistically create lift and lift 

distributions are utilized to cancel volume drag. Realizations of 

favorable interference include ring wings and the related parasol wings, 

multiple bodies (fuselages, control surfaces, wing pods) and propulsion 
33	

system interaction. For nonlifting bodies a ring wing can cancel, at 

design Mach Number, the volume wave drag of the body a la the 

“Busemann Biplane,” at the expense of increased wetted area/weight etc. 

For the lifting case the Parasol wing provides both partial cancellation of 

the body/nacelle volume wave drag and an efficient lifting surface. 

 The application of favorable interference would be facilitated by flow 

separation control and active controls. Various experimental evaluations 

of favorable wave interference have resulted in far less than the expected 

inviscid performance levels due to the detuning and drag associated with 

flow separation caused by the concomitant shock wave-boundary layer 

interactions. The plethora of flow separation approaches currently 

extant, if employed at CRUISE conditions, should enable nearly inviscid 

performance levels. One such approach is use of passive porous 

surfaces. Flow separation control utilized during cruise could also greatly 

increase the percentage of lift carried on the upper surface as expansion 

waves-as opposed to the lower surface/(shock) wave rider conventional 

approach. The use of active flow control would allow both enhanced “on 

design” and improved “off design” performance via shock locus 

tailoring. As an order of magnitude estimate, parasol favorable 

interaction SST wings can provide order of 20 percent+ improvement in 

overall lift-to-drag ratio at cruise. 

		Drag‐Due‐to‐Lift	Reduction	‐	Classical linearized theory indicates that 

elliptical loading, increased aspect ratio/span and lower lift coefficient 

values/reduced weight are the primary approaches to vortex drag due to 

lift reduction (DDLR). Obviously increasing aspect ratio/span beyond a 

certain point becomes inefficient overall due to structural penalties while 

decreased lift coefficient entails larger wings and both weight and wetted 

area/viscous drag increases. The application of the extensive alternative 

solution set for vortex DDLR has been relatively sparse (except for 

winglets) for many reasons including (depending upon the approach) 

structural weight, parasitic drag and/or power--addressable in many cases 

via creative overall aircraft configuration design - e.g. truss braced 

wings. 

 Relaxing the assumptions of classical linear theory (closed body, no 

energy addition, planar vortex sheet etc.) provides alternative vortex 

DDLR possibilities. In particular, use of non-planar lifting surfaces, e.g. 

distributing the lift vertically through various approaches such as 

upswept tips and multiple (vertically spaced) wings can provide sizable 
34	

reductions (up to order of 15 percent). Besides non-planar tips/span there 

are several interesting “natural” observations (morphology on Avians and 

Nektons) which may relate to DDLR including serrated trailing edges, 

leading edge bumps, shark caudal fin tips and sheared tips. 

 The vortex which forms at, and downstream of, the wing tip (caused by 

the tip upwash from the high pressures on the lower surface) affects a 

smaller percentage of the wing as aspect ratio increases. A characteristic 

feature of this vortex formation is flow which is at an angle to the free 

stream. Devices can therefore be inserted into this flow to 

produce/recover thrust and/or energy from this tip flow. This 

(simplistically) is the fundamental rationale behind at least four devices 

which reduce DDL. These devices can obviously also have an influence 

upon the vortex formation process itself and thus may directly influence 

DDL. These devices include tip turbines for energy extraction, winglets, 

vortex diffuser vanes, tip sails and a plethora of other tip devices such as 

wing grids, spheroid and c-tips. The vortex diffuser vane is supported by 

a spar behind the wing tip to allow the vortex to concentrate before 

interception. These devices work quite well, depending upon wing 

design and tip region loading and produce order of 5 to 15 percent 

reductions in DDL at CTOL conditions. Major application issues for 

these include, along with the “usual” concerns stated previously, possible 

utilization as control devices. 

 The following DDLR techniques are based upon either eliminating the 

tip altogether or adding mass (and /or energy) in the tip region. 

Eliminating the physical wing tips can be accomplished either via use of 

“ring wings” or joined wings and tails. Mass addition at/near the tip can 

be carried out either via tip blowing (local/remote passive or active 

bleed) or use of wingtip engines, resulting in sizable (up to 40 percent 

depending upon wing design) DDLR. Passive tip blowing could possibly 

be approached via wing leading edge ingestion (allowing increased wing 

thickness) with subsequent tip blowing used to tailor for the production 

of, and modulated to excite, virulent tip vortex instabilities at 

landing/takeoff to ameliorate the wake vortex hazard. Positioning the 

engines at the wingtip requires aerodynamic theoretical developments in 

an open thermodynamic system – as are adding energy/species as well as 

mass. Also, the engine nacelle can function as a “tip device”. 

 There is an additional possibility for DDLR. Oscillatory span load 

distributions have been employed to reduce/obviate the wake vortex 

hazard. This same approach could well yield interesting levels of DDLR 

and should be investigated for such. Other design options that need 
35	

evaluation and possible optimization for DDLR include distributed 

propulsion and circulation control of front and rear wing stagnation 

points, the latter to investigate the possibility of rotating the lift vector 

into the thrust direction. The Truss braced wing as currently conceived 

reduces DDL some 75% by the simplex expedient of doubling the span, 

enabled by the structural characteristics of the external truss, enabling a 

wholly new set of optimization parameters/ approaches. Additional 

DDLR concepts include formation flight and utilization of alternative 

sources of lift including buoyancy, and thrust vectoring. The latter begins 

to be efficacious at high supersonic speeds and is beneficial at hypersonic 

cruise. Buoyant lift typically replaces DDL with a huge increase in 

wetted area/ skin friction, producing an overall high drag with, due to the 

large sizes/ areas, undue sensitivity to “weather”. 

 Flow Control, AKA “Designer Fluid Mechanics” - Designer Fluid 

Mechanics subsumes a large number of flow control approaches and 

applications. These include Laminar Flow Control [ “Natural”/ pressure 

gradient induced at low sweep, and Forced or controlled], Mixing 

Enhancement especially for Propulsion systems components [ e.g. 

combustor, exhaust jets], Separated flow control [ especially for high lift, 

inlets, shock/boundary layer interactions], Vortex Control [ wake vortex 

hazard , Super-maneuverability], Turbulence Control [Drag Reduction, 

mixing/ combustion, sensors], Favorable Wave Interference [ Drag 

Reduction] and “Designer Fluids for internal systems. Flow Control at cruise 

to allow “Inviscid” performance optimization, smart controllers for load 

alleviation and trim drag reduction along with residual drag cleanup require 

additional study and optimization. 

 A vast number of flow control methods are available/ have been tried and 

sometimes applied. These include suction, injection, various body forces, 

surface motion[s], localized energy release, additives, surface permeability 

and heating/ cooling. Research in this arena has for some 2 decades been 

moving from passive control approaches to first active and then reactive. 

Due to systems/ applications considerations by far the bulk of the flow 

control applications have been passive devices. The now decades long 

development of smart, multi-functional materials might alter this 

conventional propensity toward passive flow control for applications. 

 Considering Laminar Flow Control, this has been under active research 

since the 1930‘s with most applications thus far being of the pressure 

gradient/ “Natural” Laminar Flow variety at relatively low Chord Reynolds 
36	

Number on GA aircraft. Until the 1960’s LFC was bedeviled by issues of 

insect remains and other roughness and waviness. As improved materials 

and approaches mitigated these concerns it was the relatively low fuel cost 

that prevented LFC from “buying its’ way” onto the aircraft in spite of 

numerous research flight experiments demonstrating feasibility/ 

performance. With the advent of “Peak Oil”/ increasing fuel costs and 

environmental concerns LFC is again under active consideration. 

 Another issue which has beset/ delayed the adoption/ utilization of some 

flow control devices has been facility capability shortfalls. In particular, 

except for NTF/ETW a lack of Reynolds Number to simulate the Wake 

Vortex Hazard has hampered the further development of devices/ 

approaches to mitigate such. The dissipation in the low Reynolds Number 

typical facility case causes quite different vortex behavior/ decay than in the 

high Reynolds number flight case. Also, the lack of low disturbance 

transonic facilities has been a problem not yet overcome for “certification” 

of LFC systems. 

 For [especially fuselage] turbulent drag reduction, a critical flow control 

arena once DDL and wing friction drag is minimized via LFC, the options, 

aside from relaminarization, are few currently. Obviously shorter and fatter [ 

without incurring wave drag] reduces wetted area. Riblets have been flight 

tested and can provide some ~8% reduction. For air flows, unlike water 

where bubbles and trace amounts of long chain polymers provide large 

reductions, decreasing turbulent skin friction a sizable amount is uphill both 

ways. Perhaps the best opportunity might be to attempt to somehow 

operationize the research observations that oscillatory transverse wall 

motions can reduce turbulent viscous drag in air flow up to the order of 45%. 

There are current no widely known approaches to producing such wall 

motions that make sense in the real world of applied technology, but not all 

possibilities have been studied well. Analysis of the nose extensions on bill 

fish suggest that they produce a turbulent flow at low Reynolds number 

with/ on low wetted area, thereby shifting the CD-Re number curve to a 

lower drag condition over the main body of the fish with its’ large wetted 

area. The potential benefit is not large but may be worth looking into for 

fuselage nose application. 
37	

Concluding Remarks 

 Civilian Aeronautics is currently in an “Interesting” period with a large 

number of increasingly serious problems and little current inclination to 

break out of the evolutionary product mode it has been in now for decades. 

The current product lines do not have sufficient “margin” to address these 

emerging problems in toto. It would appear necessary to work a shift in 

product lines to ensure success going forward. Prospective shifts include 

advanced configuration Aeronautics with factors, not percentages, 

improvements in margins/ performance and development of a wholly new 

line of business – the personal air vehicle. The ongoing exponential 

IT/Bio/Nano/Energetics/Quantum Technology Revolutions are both 

changing the “competition [especially in terms of non-physical “Virtual” 

travel] and enabling the advanced platforms and business lines required to 

meet those changes/competition issues/problems going forward. There is a 

nascent energetics technology, LENR, which may, by itself, completely 

revolutionize Civilian Aeronautics as well as just about everything else. 

Over 20 years of experiments indicating heat and transmutations with only 

sub EV inputs has established reality. We are now in the understanding and 

engineering phases, with results thereof TBD. Think fully electric wholly 

emissionless aircraft with negligible fuel fraction, MUCH less weight/vortex 

hazard, massively increased range, etc.....Energy density some 1,000 to 

1,000,000 times chemical without the need for radiation protection weights. 

Structural nano tube dry weight reductions, again by factors not percentages, 

is yet another, but lesser, source of aeronautical revolutionary change. 

 The current Situation in Civilian Aeronautics is perhaps best typified by a 

quote from an NRC report “Aeronautics is not dead and buried, only 

sleeping”. It is past time for it to wake up. 

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Emerging Options and Opportunities in Civilian Aeronautics 

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Paper address the major problems/issues with civilian aeronautics going forward, the contextual ongoing technology 

revolutions, the several emerging civilian aeronautical “Big Ideas” and associated enabling technological approaches. The 

ongoing IT Revolution is increasingly providing, as 5 senses virtual presence/reality becomes available, along with 

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considers the speed range from personal/general aviation to supersonic transports and technologies from energetics to 

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