N31AK POH, Pilots Operating Handbook


Summary, key things to know

Aft CG can be very dangerous ( "deep stall" of main wing).
The plane is a little tail heavy. see chapter Wt & Balance. There are weights, needed in the nose, for pilots < 185 lbs.
Flipping on autopilot can jerk the plane. Set it up first.
Oil is "100 Plus, SAE 50, ashless dispersant". typ 5.5 quarts. minimum 4. Jim N ran it at 4.5
The max gross landing weight is 1325. empty wt is 927 (5/12/06).
In certain smooth conditions, 1425 T.O. weight permitted. POH.
Max fuel is 52 gallons (312 lbs). 100LL only. Properly leaned around 10k', the plane burns about 5.3 gph.
Max pilot wt varies with CG but never more than 250# .
Max baggage in each strake: 100# .
Max weight in each baggage pod: 80#.
Max rpm: 2800 (people do 3000) .
Vr is 56-65 kts depending on weight.
Vx is 70 kts; Vy is 80 kts (I use 90 kts); Va is 120 kts .
Vs=Vs0=51 kts (there are no flaps), 1.3 Vs0=66 (these are estimates) .
I don't believe the 51 kts; I think stall is closer to 60
Vne is 190 kts (220mph); cruise climb: 110 kts .
Recommended glide, power off: 75-90 kts .
Can deploy nose gear below 120 kts. (I use 110).
Can deploy speed brake below 90 kts.
Landing no gusts (POH): 70-75 pattern, 65-69 final, touch 55 kts .
Landing no gusts: 80 pattern, 69-72 final, touch 55? kts.
I don't believe the POH numbers; keep it above 69kts til almost on the ground. Have seen it down to 62kts, maybe in ground effect, low gas, no pax.
Entry speed 130kts for Chandelles, Lazy Eights etc .
Max crosswind landing 20 kts, max xwind T.O. 15 kts.
CHT values: (green arc) max 435 continous, 375 nominal (?)
Oil 170-245 (green zone)
EGT values: no set range. look for changes .
Main tires: nominally 40-45 lbs, 30 minimum.
Stay away from icing conditions! The canard can't do Ice.
This (GU, old) canard airfoil can lose lift when flying into moisture.
Recommended speeds, from Bruce Hughes. may not apply to 31AK:

 75 slowest descent, power off.
130 economy cruise
 90 most flight time per gallon
 70 steepest climb
 80 best rate of climb
120 cruise climb
 80 shallowest glide
100 most miles per gallon
150 normal cruise           must be a big engine guy...



Performance: RPMs, Speed, Fuel flow rates

The plane burns about 6.3gph at 2600 rpm, 137kts TAS, 8000'DA The plane burns about 5.3gph at 2400 rpm, 120kts TAS, 8000'DA

landing
rollout
gas
pax
tempwindsource
1800'unknunkn0POH
2200'265755ktsfgh guess


KIASRPMDensity
Altitude
TAS GPH MPG Pants E-Ign?PropGas
Pax
Source
105 2200 n/a --- --- -- No No 6/07 0 -
110 2300 n/a --- --- -- No No 6/07 0 -
110 2400 n/a --- --- -- No No 6/07 0 -
120 2500 n/a --- --- -- No No 6/07 0 -
120 2600 n/a --- --- -- No No 6/07 0 -
- 2600 10k 137 6.3 26.x No No 6/07 0 9/07 ashland
120 2700 n/a --- --- -- No No 6/07 0 -
132 2800 n/a 144 6.6 24 No No 6/07 0 -
______ No No 5/08 __
______ No No 5/08 __
______ No No 5/08 __
______ No No 5/08 __
______ No No 5/08 __
______ No No 5/08 __
______ No No 5/08 __
______ No No 5/08 __
______ No No 5/08 __



Takeoff rollgas & pax, lbstemperatureheadwind, kts
1400'265 lbs65°0
1800'120 lbs75°5kt
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file: c01_summary_numbers.html