Tomcat Airframe/Engine Icing

[MrPaper]

I was recently told by someone in a DCS discord server that icing is modeled in DCS. I have noticed the anti-ice controls on the F-14 but assumed I would never really need it.

Now that I am aware icing exists in game, I am interested in testing how the Tomcat handles in different icing conditions and configurations. 

First of all, is icing modeled for the F-14? Second, does anyone know of the best way I could create heavy icing conditions in a mission editor so I could test it out?

Strangely, there are almost no videos about this on youtube other than someone flying a warbird getting some icing on the canopy.

Thanks.

[Victory205]

The answers to life's deep quandary's will not be found on youtube. 

 

While there are some answers to this question on some of the technical boards, the answers are generally speculation, but the real answer is RAM rise at high IAS obviates the need for anti-icing on aerodynamic surfaces. Fly in excess of ~400KIAS, and the frictional heating will put the leading edge temps above freezing in most ambient conditions.

 

The problem is approach. Despite having bleed air heat applied to the inlet guide vanes and bullet nose, the Tomcat would accumulate ice above the upper intake outlet doors. When the aircraft trapped, the ice would break free due to the deceleration, fly forward, and immediately get ingested by an engine a mil power during the trap.

 

I don't think that DCS puts a whole lot of emphasis on modeling icing conditions. Might be fun to pick up a load, accelerate and see if it melts. Ram rise even at high subsonic speeds is in the plus 30C range. You don't have to worry about airframe icing transonic and up. When the OAT is below ~40C, the moisture take the form of ice crystals that won't stick to the airframe.

 

Some aircraft are not as susceptible as you'd think. The Boeing 757, 787, 777 series only apply bleed air deicing to a few slats on the wing only, and probably could have been certified without airframe deice at all. 

[draconus]

What about canopy internal fog and external ice? Pilot cold/hot effects? All to put good use of our cockpit switches and make a simulation less care free.

[MrPaper]

2 hours ago, draconus said:

What about canopy internal fog and external ice? Pilot cold/hot effects? All to put good use of our cockpit switches and make a simulation less care free.

That would be awesome.

[Dragon1-1]

Pitot icing works on the A-10. It's not usually that much of a concern, but I've had a great experience when, one time I forgot to flip the relevant switch, I encountered icing conditions and had my airspeed indicator rise to a crazy value. At first I throttled it down, then I realized it's showing BS, and pretty much went to the pitot heat switch right away (it's the first thing to check when having a pitot-static failure of any sort), though I was rather surprised this was modeled.  Flipped it, flew a while, and the airspeed returned to normal. I don't know if Tomcat does that, but pitot icing is definitely supported by the engine.

[Xtorris]

I'm not sure how in-depth ice conditions are modeled for the F-14, but here is some of what I dug up from NATOPS:

 

Possible Scenarios:

• Altimeter and Mach airspeed indicators are erroneous, pitot pressure, static pressure, and total temperature inputs to the central air data computer be inaccurate. ~NATOPS F-14B 14.2
• Ice may form on inlet and ramp surfaces without any other visual indications, which may cause compressor stalls and/or FOD. ~NATOPS F-14B 14.5.11.2
• Icing conditions can cause heavy ice accumulation in the inlet ramp areas or on engine probes and the compressor face. Aircraft maneuvers and arrested landings may dislodge this accumulation and cause extensive engine FOD or failure. A straight-in field landing is preferred. Minimum power setting after landing is recommended. ~NATOPS F-14B 18.1.1
• Carefully monitor rpm and EGT indications. A reduction of rpm or an increase in EGT accompanied by a loss of thrust is an indication of engine icing. ~NATOPS F-14B 18.1.1
• NOTE: Pitot-static system failures caused by icing may input an erroneous Mach number to the air inlet control system programmer, which will result in the ramps being in the wrong position for the actual Mach number (engine stall may result). ~NATOPS F-14B 14.2
• (Preflight) Snow, ice, and frost on the aircraft surface are a major flight hazard. The result of this condition is a loss of lift and increased stall speeds. ~NATOPS F-14B 18.4.1

NATOPS talks about icing, and the possible effects on instruments, flight performance, and FOD in a few different sections...

Edited March 23, 2021 by Pacientis

[Victory205]

Have you gents found where the OAT indicator is located on the F14A or B?

[Golo]

It can be accessed by CAP if i am right. Its output is in octal, but its pretty easy to convert. Word to enter in CAP should be 71-00031. But I cant get it to work, its either not implemented or Im doing something wrong.