BFR in my CH701

Did my biennial flight review in my CH701 last Monday 18th February and it was the first time ever that I was disappointed with my 80hp Jabiru power. Having said that, it was a hot day, Density Altitude was 3,900ft, I had full tanks because I didn’t know what I was going to be asked to do and two up with the instructor 77kgs and me currently around 80kgs. Must have taken a whole 400ft to get off the ground and only made 500ft by the runways end !

MTOW sucks when you over 20% down in HP

Mine at 600kg with2 up and full tanks even with the Rotax you really feel it..especially taking off at Kingaroy on a hot day. Realistically the 701 and the savannah are really supposed to be 470kg MTOW not 520 or 600. The difference in mine with just the pax is very noticable especially the take off roll not to mention the stall speed

Did my biennial flight review in my CH701 last Monday 18th February and it was the first time ever that I was disappointed with my 80hp Jabiru power. Having said that, it was a hot day, Density Altitude was 3,900ft, I had full tanks because I didn’t know what I was going to be asked to do and two up with the instructor 77kgs and me currently around 80kgs. Must have taken a whole 400ft to get off the ground and only made 500ft by the runways end !

 I don't want to be hard on you but you should have been aware of your planes performance deficit under those conditions. That's ALL part of a BFR.  Nev

This is the BF-R I want to fly in.

            

Its CAC-13 Frame Number 1002; RAAF Serial No A46-179; No 5 Sqn. The nose painting is a comic black crow using binoculars. Plane was named Recce Robin. Pilot: 33273 Pilot Officer C. Rasmussen of Leichhardt, NSW, of No. 5 (Tactical Reconnaissance) Squadron Aircraft was converted to components January 1946.

 I don't want to be hard on you but you should have been aware of your planes performance deficit under those conditions. That's ALL part of a BFR.  Nev

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D7242CC8-482D-4D82-928A-099F8F081AA0.MOV

 You don't get proper performance charts with that type of plane generally anyhow. When there is a likely density altitude problem, pick a place on the runway to be airborne by  (at a TAS it will climb with) and abort if it's not happening. The old rule of thumb calculations from deviations from standard atmosphere work OK  but It's a while since I used them so I  quote the  allowances here., with advice to check it all out. The standard atmosphere is 1013.2 millibars  and 15 degrees C at sea level .Lapse rate 2 degrees C/1000 ft and 1 Mb equals 33 ft. of altitude change. + or minus and 1 degree is = to 200 ft + or- .

   Anytime you are at a high altitude aerodrome and it's a HOT day and there is a low pressure system about think density altitude. It affects everything  The engine is down on power  the prop s less efficient, the wing is less efficient (usually use less or no flap to get best L/D) and your indicated speed is well below your real speed and your indicated speed is what determines when it stalls, and you must accelerate longer to get there with less than normal power.. Nev

 You don't get proper performance charts with that type of plane generally anyhow. When there is a likely density altitude problem, pick a place on the runway to be airborne by  (at a TAS it will climb with) and abort if it's not happening. The old rule of thumb calculations from deviations from standard atmosphere work OK  but It's a while since I used them so I  quote the  allowances here., with advice to check it all out. The standard atmosphere is 1013.2 millibars  and 15 degrees C at sea level .Lapse rate 2 degrees C/1000 ft and 1 Mb equals 33 ft. of altitude change. + or minus and 1 degree is = to 200 ft + or- .

   Anytime you are at a high altitude aerodrome and it's a HOT day and there is a low pressure system about think density altitude. It affects everything  The engine is down on power  the prop s less efficient, the wing is less efficient (usually use less or no flap to get best L/D) and your indicated speed is well below your real speed and your indicated speed is what determines when it stalls, and you must accelerate longer to get there with less than normal power.. Nev

Mine gets better climb rate and engine cooling with flap set.

I use 50kts and a climb prop running at 3200 - 3300 rpm.

strut fairings made a big difference to climb rate too.

yes nothing can fix a hot day with full load, in that situation I plan on a climb rate around 200 - 300 fpm, its not pleasant and even a Rotax 2 stroke would probably do better. Ralph