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>Any advice on mimimum mountain emergency
approach  landing speeds for a LNC2?<

We need to understand that the airplane
sees only dynamic pressure (IAS) and
aerodynamically it would not know if it
was in the mountains or at sea level.
In other words, the proper approach IAS
at sea level would be the same at high
density altitudes for a given GW, CG and
turbulence condition.  The TAS during
approach will of course be much higher
at high density altitudes requiring a
longer rollout.  Thus the desire to lower
the approach IAS.

The second important thing to
realize is that the Lancair
is not a Champ.  A 1.2 Vs short field
approach in a Champ will not  
be safe in a Lancair.  This is another
topic.

Knowing that the aircraft's stalling
speed varies with GW, CG and bank
angle, the approach  speed is
based on the higher of what
feels comfortable and provides adequate
margin above the stalling speed. But,  
WHAT IS THE STALLING SPEED?

The difference between a short field approach
and a normal approach is nil in a Lancair.  
The major difference is the approach
flight path angle.  Certainly the AOA  
should be the same.

In effect, all approaches in a Lancair
are short field approaches.

As you know, I use AOA to gauge and
maintain a fixed margin above the stalling
speed for all approaches. Only the flight
path angle varies (throttle) depending
upon field length and approach
obstructions. All approaches are stable
below 300 feet AGL (no turns or big
changes in descent rates or IAS/AOA).

For my particular aircraft,  8.5 degrees
AOA during approach works
well and usually results in an IAS of about
79 to 85 knots. This approach AOA provides
a fixed 6.5 degrees  AOA margin above
the critical angle. These numbers will not
be the same for your aircraft.
  
For my Lancair 360 this 8.5 degree AOA for
all approaches provides enough energy to
stop the descent in the flare without excessive
float down the runway with the engine at idle
regardless of GW or CG.

Every custom built Lancair  will be slightly
different and airspeed errors will vary.  In
addition, each pilot will have to establish
their own comfort level.

Finding a good approach IAS is
like asking what IAS the aircraft stalls at.
It depends upon GW, CG, bank angle and
other factors and must not be considered
a constant ---
Nor does the bottom of the green
and white colored radial on your IAS meter
tell you where the aircraft stalls!!!!

Many of our fellow Lancair pilots that perished
in fatal accidents briefly forgot about the
limitations to flying IAS, nor were they
protected with an AOA (stall) warning.

Tip - For aerodynamics think AOA.  For speed
think GPS. For FARs think IAS.

Jim Frantz
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