CoolP asked:   Lou, regarding the icing (not on the cake) I wonder if all those de-ice and anti-ice stuff on planes is that effective when it comes to serious icing conditions.

I know that some birds are rather rigid in those, like some TwinOtter (NASA testbed), but how did a 707 for example handle severe icing, even with all her protective stuff enabled?
Was that a big threat?

And what are the first visible cues for a Captain to think of "I have to get the plane out of here, soon" instead of "we can handle that"?

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CoolP the turobjet planes do better for two reasons. First they have a lot of hot bleed air that can be used to anti-ice the wing and engine inlets. This is something the turboprop planes lack, so they use rubber boots or various chemicals. Second, the jets don't spend as much time in the icing area or altitudes. Jets generally climb faster than the slower prop planes. There are many types of ice, some much worse than others and some places where the icing is worse than in other places. Notice above I used the term "anti-ice" not de-ice. Anti-ice is used to prevent the ice from forming in the first place. De-icing infers that the ice need to build up first and then it is removed mechanically with boots or some alcohol or even electrically by heating wires. When the ice that has built up on the plane is broken off it can be a pretty nice meteor if it does not melt before it hits the ground - and I'm not talking blue ice here, that's another story!  :o

In the jet, you always want to get the anti-ice on early before the ice has a chance to build up on the nacelle and then break off and get ingested into the engine where it could do some real damage.  :-[

You ask about different planes and how they handle icing. The old 707 did pretty good in its ability to carry ice. No plane at max gross weight would do well, but at lower weights, all the Boeing planes do OK with the exception of the 727. The problem is under powered and small wings. The 757 IMO did the best when it came to icing. In real life the airport you are operating out of is also a big factor. KLGA with its short runways was a big consideration when ice was a factor. Same plane at KJFK with its long runways was a different story. The method of de-icing was also a factor. Getting de-iced at the gate is a poor way to get the job done. Getting de-iced at the departure end of the runway is a whole lot better. BTW the de-icing fluid is very expensive as nasty stuff to pour down the storm drain. A 747 could expect to cost many thousands of dollars to remove the ice or snow, and if it's done at the gate is some cases it will not last long enough to make the takeoff possible.

Usually, the first thing the pilot sees is a build-up of ice on the windshield wiper. The 707 & 727 pilots used the large nut that holds the wiper in place as a guide to how much ice was sticking to the plane. The slower turboprops and other prop planes need to let the ice accrete a bit before using the boots. If the ice forms aft of the boot that is very bad.

Lou