Icing: Mission gap between NA, TN, TC engines, HOT/COLD propellers, and CLEAN, TKS, FIKI wings?

Malibuflyer wrote:

Sure – and it is your choice with manageable risk. From legal standpoint, however, I hope we agree that in a plane that is not certified for “known and forecast icing” it is as legal as punching through this very same cloud layer VFR …

I’m sorry, but I don’t agree with you. In the situation I described, I do not expect to pick up any noticeable amount of ice and thus the flight is legal according to NCO.OP.170(a).

This shows how completely pointless these regulations are.

You can get zero icing in 10000ft of IMC, below 0C.
You can get 5cm of ice in 5 mins (enough to bring down most SEPs) in a 2000ft thick layer at -5C.
You can get 2mm of ice in 5 mins at FL180 in -20C – enough to slow one down a bit.
You can get zero ice in 10000ft of IMC, at -15C, and your engine stops

There is no such thing as being able to “expect no noticeable ice”.

Lots of good info in the icing threads listed under “Threads possibly related to this one” below.

On that question:
- The difference between FIKI-TKS and non-FIKI-TKS is none at all because the system doesn’t know if/how it is certified
- The difference between TN vs. TC with TKS is very small as icing typically happens in altitudes where the performance difference between TN and TC is very small
- The difference between (any kind of) Turbo and NA is significant: None of the Anti-Ice systems in M/SEP are really made for longer periods of time in icing, have limited capabilities in moderate icing (and of course are not at all suitable for severe icing but there even heavy metal has significant challenges) – doesn’t matter if FIKI or not. Therefore especially in stable, non convective European winter weather the ability to climb out of the icing layer is is key to define actual use.

It is hard to quantify in actual numbers, but I would say that to have a real IMC platform in Europe in Winter you need a Turbo (and anti-icing, of course).

Malibuflyer wrote:

real IMC platform in Europe in Winter you need a Turbo

Actually real winter where everything is frozen is often a lot easier regarding icing than fall and spring.

Malibuflyer wrote:

- The difference between FIKI-TKS and non-FIKI-TKS is none at all because the system doesn’t know if/how it is certified

I only owned planes with boots but my understanding was that certified systems usually have redundant pumps, often a little more capacity, fluid capacity gauges and also deice the vertical stabilizer which is often not protected on other systems.

Sebastian_G wrote:

Actually real winter where everything is frozen is often a lot easier

Fully agree – but was talking about the “European Winter” not the “real” one – just looking outside the window ;-)

Malibuflyer wrote:

My answer to that was, that with such a FIKI plane it is legal to fly in many situations where it is illegal to fly in non FIKI planes.

Why don’t we take a beer and discuss this next to a nice, warm fire burning

I come to a different conclusion wherever it seems possible to not pickup ice at all. I don’t see this prohibited, because there is no such legally binding ice forecast.

@Ibra From my point of view I see
NA + nothing < TN or TC + nothing < TN/TC + TKS or FIKI

Both regarding costs and dispatch rate. If you have a Turbo to go high (read: to stay out of possible icing conditions), but nothing to clear ice, you have to be very aware about the possible tactics to avoid flying in icing conditions and take that into account.

To be honest, I don’t think that I would do any more aggressive flying in a typical Single Engine Piston, Single Pilot having deicing means or not having them. I would end up having more or less the same dispatch rate. This changes with a more capable plane, but I would not nail that down to deicing equipment alone.

Typical icing conditions in autumn / spring show an ice condition layer of up to 4000 feet thickness. With a reasonable climb rate you can get quite quickly through such a layer, if e.g. you stop climb below (watch temperature), gain speed as much as possible and up you go. Whenever you are descending, you descend as quick as possible through this. From all that I’ve heard (and I’ve listened a lot) you will get your clearances if you don’t want to stay in a specific altitude band. This, of course, also includes to always have plan B, that is as a minimum: No ice above ground, but only at altitude.

So in more challenging conditions I would like to have a second engine, or Turbine (both donate climb rate), a second pilot, and thereafter any anti-ice equipment.

UdoR wrote:

Why don’t we take a beer and discuss this next to a nice, warm fire burning

More than happy to!

UdoR wrote:

From all that I’ve heard (and I’ve listened a lot) you will get your clearances if you don’t want to stay in a specific altitude band.

From own experience: If you tell the controller “Request climb/descend to xxx to avoid icing” they start to sound more concerned than you are and give you everything you need.