Robin DR400-100 Cadet - What's wrong?

I always assume I am the one doing something wrong before saying the airplane is not good.
So I tried the Robin DR400-100 Cadet.
It seems extremely weak as engine… I mean… seriously weak. I can’t durably climb at 500 fpm even under 4000 feet.
I attempted lean the mixture until I was loosing RPM… nothing. The engine was steadily above 2500 but it looks just super weak.
Ti climb from 5000 to 6000 feet I had to make various “jumps” literally to have the airplane to gain back speed before climbing a little more.

Possibly I did something wrong?

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It’s not a direct answer to your question but there is a freeware update to the Robin over here:

(click on aircraft at the top)

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Well thank you. Actually that’s another version with a 160 hp engine. It makes sense that a q 108 ho engine has not incredible performance but seriously it looked bugged to me… Can you really fly in safety a plane unable to climb but at 200 fpm?

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Got same issue with the Cubcraft… all default aircraft are trash, I hope is the models and not the realism the game offers…

Well in my opinion the 152 and 172 are not bad at all and the Cubs as well is pretty smooth and well behaving

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The DR400 is seriously underpowered. When your cruising speed at 2200rpm is still within the white arc and stalling is just 20-30 knots lower, when your climb rate from a cold weather 500ft MSL airfield (Hammerfest) is 100ft/min and anything above that activates the stall horn then this plane is messed up.
I would like to see this crate to depart from Courchevel Airfield at 6600ft MSL. I myself dropped it into Big Bear Lake on departure from L35 - with lean mixture setting - climb rate 0ft/min.

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Yes it’s not quite right and the Bonanza is also not good. Shame they when for the Cadet. I’ve tweaked the DR400 a bit so it performs a little better, just playing a bit with the Xcub now.

And it has an ASI with ‘knots’ written on it but it is in KM/H

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The outside scale is in KM/H, the inside scale is in knots.

Cruise on a DR400/120 is at 2400 RPM. I assume it’s pretty much the same for a DR400/100.

But 2400rpm is almost full power according to the rpm meter. That seems pretty over the top. And the oil temp then sits firmly in the middle of the red arc.

edit: I rechecked the values with the RL checklist of a 120hp DR400 (F-GDEU). The sim speedometer looks good, but for a RL 65% cruise setting at 2400rpm (75% = 2450rpm) the simulator max power seems woefully inadequate.
And even after the 50% leaned mixture the climb rate is onlz possible with 50% fuel load - with full tanks this thing might flz more like a piano.

Could you make a screenshot ? From the manual of the aircraft I use the most in the real world which is the DR400/120, we get :

  • 2400 RPM is the standard cruise torque
  • 2700 RPM is the maximum torque in normal operation
  • 2800 RPM is the maximum continuous torque available

Regarding oil temp, the maximum temperture is 118°C. By the way I don’t understand the fact of introducing the DR400/100 in the sim, it’s not even used anymore. Most clubs here in France (if not every clubs) have DR400/120 as the most affordable aircraft to fly. I’ve never ever seen any DR400/100 in the hood.

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Hi,
I was so disapointed to fly the DR400 with only 118hp, especially at high elevation airport that I did some digging and modifying the CFG of aircraft to add some power.
I just took some line from the C172 engines and pasted it in the DR400 engin.cfg

In piston engine:
power_scalar = 1 ; Piston power scalar
cylinder_displacement = 90 ; Cubic inches per cylinder
compression_ratio = 8.5 ; Compression ratio
number_of_cylinders = 4 ; Number of cylinders
max_rated_rpm = 2700 ; Max rated RPM
max_rated_hp = 180 ; Max rated HP

and some line below

max_rpm_mechanical_efficiency_scalar = 0.86 ; Scalar on maximum RPM mechanical efficiency
idle_rpm_mechanical_efficiency_scalar = 1
max_rpm_friction_scalar = 0.55 ; Scalar on maximum RPM friction

then in the prop section:
thrust_scalar = 1.15 ; Propeller thrust scalar
propeller_type = 1 ; 0=Constant Speed, 1=Fixed Pitch
propeller_diameter = 6.3 ; Propeller Diameter, (feet)
propeller_blades = 2 ; Number of propeller blades
propeller_moi = 3 ; Propeller moment of inertia

So now you have a brand new DR400 180hp ! lol

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I just pancaked the Robin after trying to fly with full fuel and a bit of baggage, about 100lbs below MTOW. I did an extra long takeoff run to gather speed, but once airborne (with flaps) my IAS was bleeding off like flying through syrup (all with recommended 50% lean mixture).
edit: 2nd attempt with flaps retracted after airborne brought same result.
On the sim speedometer the green arc extends from 2000 to around 2550rpm with the red line at 2600rpm (dumb user struggles to make screenshot, sry).

It seems that with max takeoff weight this thing is not staying arborne for long, if at all.

I tried your engine boost and it worked nicely - sadly the sim froze, again.

edit: 2nd attempt, this time with full fuel, 2 pilots and 50lbs luggage, 100lbs below MTOW - no problems

It’s good to replace the engine with a 180 HP. Still if the 108 HP exist for real it should be nice to have it properly modelled and I’m pretty sure the real one can’t be flying in safety with a 100 fpm climbing rate.

At MTOW minus 100lbs this crate does not even fly. It behaves like one of the things they show in the b/w prologue of “Those Magnificent Men in their Flying Machines”.

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Thats what make me suspect there’s some thing more severe in the flight model. If a real plane should fly with this parameters as well a simulated one should…

All the planes I have been flying in MSFS (well just 2, the SAV Cub and the Robin) start with tanks only 50% full. With that load the Robin barely manages to get airborne with flaps down. If you retract flaps early enough - a bad habit in RL - you can manage to gain enough speed to achieve a modest climb. With flaps down, first your airspeed goes down, then your altitude. When leaning (even when departing from sea level airfields) to 50% you can manage a (n.b. no flaps and 50% fuel) half-baked climb rate. All the while your oil temp is smack in the middle of the red arc.

I really wonder who flew this crate during testing and said: “Well, looks good…”. No, Sir, it definitely does not.

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50% leaned at SL is too much AFAIR and will decrease performance even more than leaving it at 100%.
Have you tried 75%?