<s>
ATF	B-Application
(	O
Advanced	O
Tactical	O
Fighter	O
)	O
is	O
a	O
video	O
game	O
released	O
in	O
1988	B-Application
for	O
the	O
ZX	B-Operating_System
Spectrum	I-Operating_System
,	O
Commodore	O
64	O
and	O
Amstrad	B-Device
CPC	I-Device
by	O
Digital	O
Integration	O
Ltd	O
.	O
</s>
<s>
The	O
player	O
takes	O
control	O
of	O
Lockheed	O
's	O
YF-22A	O
Advanced	O
Tactical	O
Fighter	O
(	O
the	O
craft	O
which	O
later	O
became	O
the	O
F-22	B-Application
Raptor	I-Application
)	O
in	O
a	O
fictional	O
war	O
between	O
two	O
rival	O
factions	O
.	O
</s>
<s>
The	O
display	O
is	O
a	O
third-person	O
view	O
showing	O
the	O
player	O
's	O
ATF	B-Application
,	O
which	O
remains	O
stationary	O
on	O
screen	O
as	O
the	O
scenery	O
scrolls	O
past	O
it	O
,	O
which	O
takes	O
up	O
most	O
of	O
the	O
screen	O
.	O
</s>
<s>
A	O
head-up	B-Application
display	I-Application
is	O
superimposed	O
on	O
the	O
main	O
screen	O
;	O
this	O
shows	O
engine	O
thrust	O
,	O
the	O
ATF	B-Application
's	O
speed	O
,	O
ground	O
height	O
and	O
altitude	O
,	O
along	O
with	O
the	O
missile	O
system	O
available	O
,	O
direction	O
of	O
flight	O
and	O
a	O
target	O
's	O
range	O
and	O
bearing	O
.	O
</s>
<s>
The	O
right-hand	O
side	O
is	O
devoted	O
to	O
the	O
"	O
on-board	O
flight	O
computer	O
"	O
which	O
shows	O
enemy	O
positions	O
on	O
a	O
world	O
map	O
,	O
the	O
status	O
of	O
weapon	O
systems	O
and	O
the	O
ATF	B-Application
itself	O
.	O
</s>
<s>
Below	O
the	O
main	O
display	O
is	O
a	O
panel	O
which	O
displays	O
status	O
reports	O
,	O
and	O
below	O
that	O
indicators	O
for	O
fuel	O
level	O
,	O
enemy	O
missile	O
lock	O
on	O
,	O
"	O
terrain	O
following	O
"	O
status	O
,	O
"	O
automatic	O
landing	O
"	O
availability	O
(	O
activated	O
when	O
the	O
ATF	B-Application
enters	O
the	O
catchment	O
area	O
surrounding	O
allied	O
bases	O
)	O
,	O
and	O
undercarriage	O
status	O
.	O
</s>
<s>
The	O
"	O
terrain	O
following	O
RADAR	O
"	O
prevents	O
the	O
ATF	B-Application
from	O
colliding	O
with	O
the	O
ground	O
but	O
reduces	O
the	O
craft	O
's	O
velocity	O
.	O
</s>
<s>
The	O
program	O
code	O
for	O
the	O
Sinclair	B-Operating_System
Spectrum	I-Operating_System
version	O
was	O
written	O
on	O
an	O
IBM	O
AT-compatible	O
computer	O
using	O
a	O
macro	B-Language
assembler	I-Language
,	O
while	O
the	O
graphics	O
were	O
designed	O
on	O
an	O
Atari	B-Device
ST	I-Device
,	O
then	O
downloaded	O
onto	O
the	O
IBM	B-Operating_System
AT	I-Operating_System
,	O
before	O
being	O
downloaded	O
to	O
the	O
Spectrum	O
and	O
debugged	O
using	O
a	O
specially	O
developed	O
monitor	O
.	O
</s>
