Anti-Ice on Combat Aircraft

[Charles Talleyrand]

We have an A-4 and a B-52 on the airport here. Neither seems to have
an anti-ice system as far as I can see (of course the B-52's wing is rather
above my head, and currently covered in snow).

Do Air Force/Navy planes have de-ice equipment? What happens
when the radar dome gets coated in ice while flying through cold clouds?

-Thanks

[John Pelchat]

"Charles Talleyrand" > wrote in message >...
> We have an A-4 and a B-52 on the airport here. Neither seems to have
> an anti-ice system as far as I can see (of course the B-52's wing is rather
> above my head, and currently covered in snow).
>
> Do Air Force/Navy planes have de-ice equipment? What happens
> when the radar dome gets coated in ice while flying through cold clouds?
>
> -Thanks

Charles,

I am not sure about the specifics for the B-52 or the A-4, but many
jets use hot bleed air ducted from the engine(s) to warm the leading
edge and thus prevent/remove ice building on up wings and other
aero-surfaces. Pneumatic boots common on (piston and jet) prop
aircraft have problems at higher jet speeds (probably related to drag
and durability). Maybe a few scooter, buff, and blow-torch drivers
will elighten us all.

Best to all

John Pelchat

[John R Weiss]

"Charles Talleyrand" > wrote...
> We have an A-4 and a B-52 on the airport here. Neither seems to have
> an anti-ice system as far as I can see (of course the B-52's wing is rather
> above my head, and currently covered in snow).
>
> Do Air Force/Navy planes have de-ice equipment? What happens
> when the radar dome gets coated in ice while flying through cold clouds?

IIRC the A-4 had engine anti-ice and heated windscreen and pitot tube. No wing
anti-ice. Don't know about the B-52.

Engine anti-ice is necessary in more environmental conditions than is wing
anti-ice. WAI installations are also comparatively heavy and power-hungry.

FWIW, I turned on the WAI in the 747 for the second time in 5 years just the
other day -- more out of curiosity than need; we use nacelle anti-ice routinely.
We were picking up a bit on the descent into ANC, and wanted to see if it made
any difference. Found that the ice on the outboard leading edges melted
first...

[BUFDRVR]

>IIRC the A-4 had engine anti-ice and heated windscreen and pitot tube. No
>wing
>anti-ice. Don't know about the B-52.

The B-52 uses bleed air to prevent ice build up on the inlets, inlet guide
vanes, EPR inlet probes and, on the H model, the cowling. I'm not sure if you
can see anything visably though, most of it is internal.


BUFDRVR

"Stay on the bomb run boys, I'm gonna get those bomb doors open if it harelips
everyone on Bear Creek"

[Bob Liberty]

Think the 135 was similar

ole nav
"BUFDRVR" > wrote in message
...
> >IIRC the A-4 had engine anti-ice and heated windscreen and pitot tube.
No
> >wing
> >anti-ice. Don't know about the B-52.
>
> The B-52 uses bleed air to prevent ice build up on the inlets, inlet guide
> vanes, EPR inlet probes and, on the H model, the cowling. I'm not sure if
you
> can see anything visably though, most of it is internal.
>
>
> BUFDRVR
>
> "Stay on the bomb run boys, I'm gonna get those bomb doors open if it
harelips
> everyone on Bear Creek"
>

[[email protected]]

"Bob Liberty" > wrote:

>Think the 135 was similar
>
>ole nav
>"BUFDRVR" > wrote in message
...
>> >IIRC the A-4 had engine anti-ice and heated windscreen and pitot tube.
>No
>> >wing
>> >anti-ice. Don't know about the B-52.
>>
>> The B-52 uses bleed air to prevent ice build up on the inlets, inlet guide
>> vanes, EPR inlet probes and, on the H model, the cowling. I'm not sure if
>you
>> can see anything visably though, most of it is internal.
>>
>>
>> BUFDRVR
>>

The Argus (ASW aircraft slightly bigger than a C-130) was used in
severe icing conditions (low level over the North Atlantic) and
was well equipped with anti-icing and deicing equipment. They had
huge gas fired heaters (600 BTU each) one for each wing and one
for the tail, plus a 300 BTU one for cabin heating. They also had
numerous anti-ice mats for cowlings and other air-scoops plus
electrical prop deicers and 'Nesa windscreens'. I've flown
through some horrendous icing conditions believe me. The
replacement aircraft for the Argus (P-3 Aurora/Orion) has great
wing anti-icers utilizing engine bleed air, very effective
indeed.

-Gord.

"I'm trying to get as old as I can,
and it must be working 'cause I'm
the oldest now that I've ever been"

[Ron]

>The Argus (ASW aircraft slightly bigger than a C-130) was used in
>severe icing conditions (low level over the North Atlantic) and
>was well equipped with anti-icing and deicing equipment. They had
>huge gas fired heaters (600 BTU each) one for each wing and one
>for the tail, plus a 300 BTU one for cabin heating. They also had
>numerous anti-ice mats for cowlings and other air-scoops plus
>electrical prop deicers and 'Nesa windscreens'. I've flown
>through some horrendous icing conditions believe me. The
>replacement aircraft for the Argus (P-3 Aurora/Orion) has great
>wing anti-icers utilizing engine bleed air, very effective
>indeed.
>
>-Gord.

Low level severe icing, over the north atlantic in the winter, does not sound
like something for the faint of heart...


Ron
Pilot/Wildland Firefighter

[Dave Holford]

Ron wrote:
>
> >The Argus (ASW aircraft slightly bigger than a C-130) was used in
> >severe icing conditions (low level over the North Atlantic) and
> >was well equipped with anti-icing and deicing equipment. They had
> >huge gas fired heaters (600 BTU each) one for each wing and one
> >for the tail, plus a 300 BTU one for cabin heating. They also had
> >numerous anti-ice mats for cowlings and other air-scoops plus
> >electrical prop deicers and 'Nesa windscreens'. I've flown
> >through some horrendous icing conditions believe me. The
> >replacement aircraft for the Argus (P-3 Aurora/Orion) has great
> >wing anti-icers utilizing engine bleed air, very effective
> >indeed.
> >
> >-Gord.
>
> Low level severe icing, over the north atlantic in the winter, does not sound
> like something for the faint of heart...
>
> Ron
> Pilot/Wildland Firefighter


It's interesting when large chunks fly off a prop blade.

Dave

[[email protected]]

(Ron) wrote:

>>The Argus (ASW aircraft slightly bigger than a C-130) was used in
>>severe icing conditions (low level over the North Atlantic) and
>>was well equipped with anti-icing and deicing equipment. They had
>>huge gas fired heaters (600 BTU each) one for each wing and one
>>for the tail, plus a 300 BTU one for cabin heating. They also had
>>numerous anti-ice mats for cowlings and other air-scoops plus
>>electrical prop deicers and 'Nesa windscreens'. I've flown
>>through some horrendous icing conditions believe me. The
>>replacement aircraft for the Argus (P-3 Aurora/Orion) has great
>>wing anti-icers utilizing engine bleed air, very effective
>>indeed.
>>
>>-Gord.
>
>Low level severe icing, over the north atlantic in the winter, does not sound
>like something for the faint of heart...
>
>
>Ron
>Pilot/Wildland Firefighter

....but we were young and foolish then (or perhaps faint of
intelligence?) and that's what gave rise to my sig :)...

-Gord.

"I'm trying to get as old as I can,
and it must be working 'cause I'm
the oldest now that I've ever been"

[WaltBJ]

The only fighter I ever flew with surface anti-ice was the F86D/L. The
only time I ever heard of anybody in the outfit using it he got
serious damage to electrical circuitry inside the wing from a break in
the ducting.
FWIW if the indicated airspeed is around 300 knots the ram temp rise
is high enough to prevent icing. Most jets I know of do have engine
anti-ice and heated windscreens.
Walt BJ

[[email protected]]

Dave Holford > wrote:

>
>It's interesting when large chunks fly off a prop blade.
>
>Dave

Hell yes, wasn't that a hoot, especially when you were near some
young inexperienced guy, you could get quite a reaction outta him
with a horrified facial expression. :)

-Gord.

"I'm trying to get as old as I can,
and it must be working 'cause I'm
the oldest now that I've ever been"

[Ron]

>>
>>It's interesting when large chunks fly off a prop blade.
>>
>>Dave
>
>Hell yes, wasn't that a hoot, especially when you were near some
>young inexperienced guy, you could get quite a reaction outta him
>with a horrified facial expression. :)

When I did cloud seeding flights, our Cessna 340s and Piper Cheyennes were
pretty beat up in that part of the fuselage, from ice being flung from the
props.

We were looking for super cooler water droplets, which of course were going to
freeze to the aircraft, since our target zone for temps was -5 to -10C.

However that was over land, around 20,000 ft, and not far from airports.

Doing it over the north Atlantic at night at low level in severe icing still
sounds like insanity :)


Ron
Pilot/Wildland Firefighter

[[email protected]]

(WaltBJ) wrote:

>The only fighter I ever flew with surface anti-ice was the F86D/L. The
>only time I ever heard of anybody in the outfit using it he got
>serious damage to electrical circuitry inside the wing from a break in
>the ducting.
>FWIW if the indicated airspeed is around 300 knots the ram temp rise
>is high enough to prevent icing. Most jets I know of do have engine
>anti-ice and heated windscreens.
>Walt BJ

Learned something new I guess, I'd never have thought that 300 kt
would have done it...

-Gord.

"I'm trying to get as old as I can,
and it must be working 'cause I'm
the oldest now that I've ever been"

[Rick]

wrote:

> Learned something new I guess, I'd never have thought that 300 kt
> would have done it...


300 knots adds about 16 degrees C. in the middle altitudes where most
nasty stuff is found.

Rick

[Mortimer Schnerd, RN]

Gord Beaman wrote:

>> It's interesting when large chunks fly off a prop blade.
>
> Hell yes, wasn't that a hoot, especially when you were near some
> young inexperienced guy, you could get quite a reaction outta him
> with a horrified facial expression. :)


The first time I ever heard that I was flying at 10,000 feet against a brutal 60
knot headwind trying to make my way to Cincinnati with a load of auto parts in
the middle of the night. Mountains below; no oxygen above. I hadn't slept in
24 hours. Naturally I was by myself. No autopilot.

Frequent worried looks out at the wing with my flashlight.... popping the boots
from time to time.... occasional squirts of alcohol on the windshield... BOOM!
The fuselage got machine gunned as the props deiced.

The size of my sphincter was in inverse proportion to the magnitude of the BOOM.
A lovely evening.

There's more to the story: I fell asleep on the way back to Charlotte at about
0430 flying with a partial panel (AI had failed shortly after takeoff) while
running on the aux tanks. I was woken rather rudely by the left engine
quitting, and then while I was fumbling with the boost pumps and changing tanks,
the right engine quit as well. I remember the feeling of satisfaction I had
noting how closely I had leaned the two engines that they would run dry within
30 seconds or so of one another. I promised God if he would let me live, I
would never fall asleep again while I was flying.

I lied. God got me for it, too. One of the damned brakes failed on landing. I
missed my turnoff and an USAir jet had to go around. I bet he liked that.


--
Mortimer Schnerd, RN


http://www.mortimerschnerd.com

[Scet]

"Gord Beaman" > wrote in message
...
> "Bob Liberty" > wrote:
>
> >Think the 135 was similar
> >
> >ole nav
> >"BUFDRVR" > wrote in message
> ...
> >> >IIRC the A-4 had engine anti-ice and heated windscreen and pitot tube.
> >No
> >> >wing
> >> >anti-ice. Don't know about the B-52.
> >>
> >> The B-52 uses bleed air to prevent ice build up on the inlets, inlet
guide
> >> vanes, EPR inlet probes and, on the H model, the cowling. I'm not sure
if
> >you
> >> can see anything visably though, most of it is internal.
> >>
> >>
> >> BUFDRVR
> >>
>
> The Argus (ASW aircraft slightly bigger than a C-130) was used in
> severe icing conditions (low level over the North Atlantic) and
> was well equipped with anti-icing and deicing equipment. They had
> huge gas fired heaters (600 BTU each) one for each wing and one
> for the tail, plus a 300 BTU one for cabin heating. They also had
> numerous anti-ice mats for cowlings and other air-scoops plus
> electrical prop deicers and 'Nesa windscreens'. I've flown
> through some horrendous icing conditions believe me. The
> replacement aircraft for the Argus (P-3 Aurora/Orion) has great
> wing anti-icers utilizing engine bleed air, very effective
> indeed.
>
> -Gord.
>
> "I'm trying to get as old as I can,
> and it must be working 'cause I'm
> the oldest now that I've ever been"

The engines on the P3 also Anti-ice "themselves". One switch per engine
opens two solenoid valves, one of which directs air to the air scoop, the
other causes a pressure imbalance in two valves fitted at the nine and three
o clock positions on the air inlet housing. These two valves anti-ice the
air inlet housing, IGV's CIP and CIT probes and the torque meter shroud. The
solenoids are energised closed so are fail safe. Two thermal switches wired
in series, are fitted to the air scoop and torque meter lines, they
illuminate an anti-ice light in the flight station within 60 -90 seconds of
selection when the temperature of the pipe reaches 93 Degs C. A TIT increase
of approxamately 22 Degs C and a SHP drop of Approx. 9% will also be noted.
The props are electrically de-iced with the first 22 " of the spinner
anti -iced. :-)

Scet

[[email protected]]

"Scet" > wrote:

>The engines on the P3 also Anti-ice "themselves". One switch per engine
>opens two solenoid valves, one of which directs air to the air scoop, the
>other causes a pressure imbalance in two valves fitted at the nine and three
>o clock positions on the air inlet housing. These two valves anti-ice the
>air inlet housing, IGV's CIP and CIT probes and the torque meter shroud. The
>solenoids are energised closed so are fail safe. Two thermal switches wired
>in series, are fitted to the air scoop and torque meter lines, they
>illuminate an anti-ice light in the flight station within 60 -90 seconds of
>selection when the temperature of the pipe reaches 93 Degs C. A TIT increase
>of approxamately 22 Degs C and a SHP drop of Approx. 9% will also be noted.
>The props are electrically de-iced with the first 22 " of the spinner
>anti -iced. :-)
>
>Scet
>
Yes, very similar to the system on the Convair 580 that used to
be used in the RCAF. Almost identical engines and props used on
C-130/P-3's.

Incidentally, there was a good story in Canada's "Maritime Patrol
Aviation" magazine in the "Mission Impossible" section about this
USN P-3 which had been flown (with nr 1 loitered) for awhile in
cloud with the engine anti-ice off (against the advice of the
F/E). When the anti-ice was finally turned on ice shedding from
the intake killed nr 2 and in the excitement nr 1 was badly
overtemped on startup and during this kerfluffle nr 4 flamed out
from ice shedding. So in just a matter of seconds they were down
to one engine (nr 3) with a 4 engined a/c. They tried a restart
on nr 2 and got it going after awhile so they're now back to two
running. The shaken crew elected to land in that condition. It
was discovered that the nr 3 engine anti-ice valve had failed
sometime in the past and that's why it didn't quit. (failsafe as
you mentioned). WooHoo!...

-Gord.

"I'm trying to get as old as I can,
and it must be working 'cause I'm
the oldest now that I've ever been"

[Charles Talleyrand]

"WaltBJ" > wrote in message om...
> The only fighter I ever flew with surface anti-ice was the F86D/L. The
> only time I ever heard of anybody in the outfit using it he got
> serious damage to electrical circuitry inside the wing from a break in
> the ducting.
> FWIW if the indicated airspeed is around 300 knots the ram temp rise
> is high enough to prevent icing. Most jets I know of do have engine
> anti-ice and heated windscreens.


So does this mean that most fighter jets cannot be combat useful when
there are lots of wet cold clouds around. That must be a common condition
in some parts of the world.

Do the Russians have any more anti-ice than this? They might have
more need.

[M. J. Powell]

>> "Bob Liberty" > wrote:
>>
Snip

>> >>
>>
>> The Argus (ASW aircraft slightly bigger than a C-130) was used in
>> severe icing conditions (low level over the North Atlantic) and
>> was well equipped with anti-icing and deicing equipment. They had
>> huge gas fired heaters (600 BTU each) one for each wing and one
>> for the tail, plus a 300 BTU one for cabin heating.

Are you sure about those figures? My Central Heating boiler is rated at
80,000 BTU.

Mike
--
M.J.Powell

[s.p.i.]

(WaltBJ) wrote in message >...
> The only fighter I ever flew with surface anti-ice was the F86D/L. The
> only time I ever heard of anybody in the outfit using it he got
> serious damage to electrical circuitry inside the wing from a break in
> the ducting.
> FWIW if the indicated airspeed is around 300 knots the ram temp rise
> is high enough to prevent icing. Most jets I know of do have engine
> anti-ice and heated windscreens.
> Walt BJ

What were the details of that B-1 loss some years ago due to icing?
Sometimes ya gotta slow down.
Also, these have been numerous UAV losses to icing and several helos
as well. That video shot of bin Laden a couple of years ago showed his
kids having a picnic around a destroyed MH-53 rotor head that ended up
where it was due to icing
Also, I would think this 'bus was tooling along at m.78 or so when he
found this ice today. This is pretty high to find ice this time of the
where he was...
UA /OV DPR/TM 1530/FL310/TP A306/SK OVC-TOP310/IC LGT-MOD BLO 310/NEG
ABV 310
Granted, I don't know what the indicated was since I'm not near a
flight planning system, but big iron is not immune to airframe icing
in cruise-even with ram rise factored in. Last week I saw a Airep out
on A300 in the Atlantic for moderate "almost severe" at FL350 in one
of the frontal systems.

[[email protected]]

"M. J. Powell" > wrote:

>>> "Bob Liberty" > wrote:
>>>
>Snip
>
>>> >>
>>>
>>> The Argus (ASW aircraft slightly bigger than a C-130) was used in
>>> severe icing conditions (low level over the North Atlantic) and
>>> was well equipped with anti-icing and deicing equipment. They had
>>> huge gas fired heaters (600 BTU each) one for each wing and one
>>> for the tail, plus a 300 BTU one for cabin heating.
>
>Are you sure about those figures? My Central Heating boiler is rated at
>80,000 BTU.
>
>Mike

Oops!...forgot to add the 'k' didn't I?... :)

They're 600k and 300k (600,000 and 300,000 BTU)

Thanks Mike!...

-Gord.

"I'm trying to get as old as I can,
and it must be working 'cause I'm
the oldest now that I've ever been"

[Scet]

"Gord Beaman" > wrote in message
...
> "Scet" > wrote:
>
> >> >
> Yes, very similar to the system on the Convair 580 that used to
> be used in the RCAF. Almost identical engines and props used on
> C-130/P-3's.
>
> Incidentally, there was a good story in Canada's "Maritime Patrol
> Aviation" magazine in the "Mission Impossible" section about this
> USN P-3 which had been flown (with nr 1 loitered) for awhile in
> cloud with the engine anti-ice off (against the advice of the
> F/E). When the anti-ice was finally turned on ice shedding from
> the intake killed nr 2 and in the excitement nr 1 was badly
> overtemped on startup and during this kerfluffle nr 4 flamed out
> from ice shedding. So in just a matter of seconds they were down
> to one engine (nr 3) with a 4 engined a/c. They tried a restart
> on nr 2 and got it going after awhile so they're now back to two
> running. The shaken crew elected to land in that condition. It
> was discovered that the nr 3 engine anti-ice valve had failed
> sometime in the past and that's why it didn't quit. (failsafe as
> you mentioned). WooHoo!...
>
> -Gord.
>
> "I'm trying to get as old as I can,
> and it must be working 'cause I'm
> the oldest now that I've ever been"

Hi Gord, I take it that you mean that #1 was loitered and no engine anti-ice
was selected for any of the engines. If an engine is shut down it cannot
recieve bleed air from another source for anti-ice purposes. The frequency
of illumination of the "Icing" light on the vertical annunciator should of
alerted the crew that turning anti-ice off wouldn't be a wise move, or if it
wasn't on then maybe it should be turned on. The fact that #3 anti-ice valve
failed sometime in the past and wasn't noticed or if it was noticed was not
not replaced is a worry. The crew should have noticed that TIT only went up
11-12 Deg C and a SHP drop of 4-5% instead of the usual 22-24 Deg C TIT rise
and 9% SHP drop. The "Anti-icing"light, on the propand engine ice control
panel, would of still illuminated as the thermal switch would of still been
made. If the power lever was above cross over, TIT would still roll up then
back, SHP indications would be the same as below cross over.

At the end of the day though, it is great that the crew made it back and
hopefully lessons are learned.

Scet