Blackhawk Intake Cowl Deicing System

[BPBEN]

I have conflicting information regarding the intake cowl deicing system on the Blackhawk. Brown Helicopter says its a bleed air system, and Redstone Arsenal's Engineer who I am speaking to says it is an electric system such as the one on the S-61.

Specific information would be greatly appreciated.

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[212man]

I suspect they are talking at cross purposes and describing different functions. I don't know the S-60 system but I would guess it's very similar to the S-92. This is the description from the RFM for engine anti-icing - you will see that both electrical and bleed air is used for different stages of the intake process:

The inlets are anti-iced by electrically (ac) powered, dual zone, heating mats imbedded in the inlets. An inlet anti-ice controller, located in each engine inlet duct, regulates the two heating mats to ensure that the inlet surface is greater than 4° C. If one zone should fail, the remaining zone will continue to function but may not be able to completely anti-ice the inlet. The INLET 1 A-ICE FAIL and/or INLET 2 A-ICE FAIL cautions illuminate when there is a problem with the electrical inlet heating mats.

The compressor inlet guide vanes and the IPS axial inlet are anti-iced by engine bleed air. The amount of engine bleed air that is routed to the anti-ice system is determined by the FADEC based on Ng and T1 (the temperature sensed at the engine inlet). The ENG 1 A-ICE DGRD and/or ENG 2 A-ICE DGRD cautions illuminate when there is a problem with the bleed air portion of the system.

[BPBEN]

That makes sense to me. I have the IPC and it is difficult to see what is under a cutaway in the cowl: I don't have enough detail. However, it appears that there is an RGB driving the rotor at the front of the engine, sitting on a shaf, and there wouldn't seem to be enough room for sufficient ducting off of the compressor to heat that cowl.

If you can a diagram of the piece, that would be appreciated: I'm waiting for one from Redstone Arsenal now ... but they can be quite slow.

I am making a different system, under an STC, for the S61 Sea King .. similar to systems I make for planes such as the Convair, Electra, C-130/L100, Fokker, Saab, and others. I'm looking for helicopter applications that utilize a heated mat system such as what you have described: That wire based system is substantially inferior to the system that we make, which utilizes a flame spray of metal that is wider and therefore more resistant to FOD. Ben Kalka ... Jay Dee Aircraft Supply Co., Inc.

[Blackhawk9]

212 man is correct for the S-92 but it's not the same on the Black Hawk, The S-70 has both engine inlet and Aiframe engine intake (intake cowl assy) supplied with engine Bleed air for anti ice, the engine intake has bleed air from the Anti-ice start bleed valve come thru a swirl vane air tube into the swirl frame and into the engine intake vanes it exits the trailing edge of the 12 swirl vanes (similar on T700 and CT7-8A), the Airframe engine intake(intake cowl) anti-ice is bleed air from the customer bleed on the side of the compressor case going thru a tube to the inlet Anti-ice valve ( mounted in the intake cowl) it then goes into the cavity behind the inlet mouth and exits thru the gill slits on the inboard side , the S-92 is electric for this part as iv'e been told the FAA would not approve the Black Hawk style intake with bleed air for both anti-ice sections for civil use and why a S-92 intake is a damn side heavier than a Black Hawk intake with its heated mats in it.

[BPBEN]

I am a bit confused by Blackhawk 9's response, partly because I am not sufficiently informed about the various Blackhawk variants, civilian and otherwise.

Does this mean that the standard UH-60 Blackhawk that the military uses has both bleed air and a heated mat? What other models, both of the Blackhawk and other helicopters, do you know of that have such a heated mat system? And, if you have a drawing of the heated mat component(s), could you get them to me.
[email protected] for off site messages.

Thanks for the help.

Ben Kalka

[rjsquirrel]

The H-60 family helicopters are all alike in the bellmouth heat department. The bellmouth (the entire black thingy that lays against the fuselage and also rings the inlet) is heated by bleed air, as can be told by the rise in T4.5 when the bellmouth heat is selected on (about 45 degrees!).

This system works well as evidenced by millions of hours, but in a low powered descent, there isn't much bleed air, so the system can't guarantee complete anti-ice.

For this reason, the S92 came out with an electrically heated bellmouth, which is heated fully in all flight conditions, and is fully FAA approved.

[BPBEN]

Does that mean that the standard UH-60 does not have any electrical heat on the intake cowl? Has there been retrofitting of the models?

Yours,

BEN

[widgeon]

Invest 14.95 here

UH-60 Blackhawk Helicopter (http://www.emilitarymanuals.com/uh-60blackhawk.html)

TM 1-1520-237-10 Operator's Manual For UH-60A, UH-60L and EH-60A Helicopters

This manual is included in the CD.

Also if you are serious read this link http://www.redstone.army.mil/cmo/caslgeneral.doc#repair1

Also , if it is a spare part you should find it on this list
Aviation Repair Parts Data (http://trol.redstone.army.mil/cgi-bin/cmo/get_spare_repair_data_a.pl?p_column=WSC&p_order=ASC&p_history_search=&p_nsn_search=&p_apn_search=&p_date_search=)

And if you are lucky and you register , you may be able to view the top drawing

A tip if you can find the Nato Stock Number for the intake , searches will be easier .

[rjsquirrel]

BPBEN,

No electrical bellmouth or engine front frame heat on an H-60 (Black Hawk or Sea Hawk). No retrofit (who would bother to pay the price to send the design back to an icing tunnel for qualification?)

[JohnDixson]

The U.S. Army had placed significant emphasis on maintainability and reliability in its requirements for the UTTAS ( Utility Tactical Aircraft System ).

At Sikorsky, we had extensive experience with electrically heated inlets on both the S-61 and S-65 series, and the design team was convinced that field reliability could be measurably improved with a pneumatic/bleed air system. Remember, this was a 1972 design choice.

Thanks,
John Dixson

[ramen noodles]

If I recall correctly, the power needed to heat the engine bellmouths on an H-60 is about 45 degrees T4.5, or 11% torque or around 280 horsepower. This is about the power needed by the elevators on the Petronis Towers!