T/O Trim setting

[oldngray 8]

Have not been able to establish a trim setting for T/O that allows for smooth rotation. Almost impossible to get airbourne without full rear deflection of yoke. Typical takeoff at any weight am still hard on the ground at 120k. Trim set at rear of T/O marks.

Don't know if I have corrupted installation or not. 

What trim setting do some of you use and at what speed do you rotate the 421.

 

[Bert Pieke 7,585]

A notch of flaps?

[fppilot 4,371]

4 hours ago, oldngray said:

What trim setting do some of you use and at what speed do you rotate the 421.

 

In your FSX installation you should find a Carenado folder with subfolders for each of their models you have installed.  There should be a series of pdf documents/guides in each of those folders.  Carenado has not been consistent model-to-model about the list of guides and not consistent about the contents of similarly named documents.  I would look first in a document that is titled Normal Operations or includes the word "checklist".  What you are looking for is the speed to rotate or V_R speed.  For the slightly larger F406 Caravan II Carenado indicates a V_R speed of 198 Knots IAS.  Many other twins are in that range as they want the speed if needed to overcome an engine out emergency.

Bert is spot on with the mention of a notch of flaps.  Also, you are aware that you take off on the active runway, whichever is best into the wind./

[LRBS 948]

Something is terribly wrong here.

Not even a 747 or A380 has a Vr of 198 Kts at max t.o. weight. A C421 economy cruise is about 194 kts. The issue here might be out of cg situation due to improper weight loading distribution or just a corrupt file. And yes, 421 has a flaps setting for t.o.

[Bert Pieke 7,585]

The provided documentation calls for 100 KIAS takeoff and initial climb speed.

I set the trim indicator on the "O" of T.O. and add one notch of flaps.

Rotate at 100 kts and liftoff at 110 with slight back pressure on the yoke.

Edited January 23, 2022 by Bert Pieke

[JesC 88]

For the sake of clarity, note that the POH takeoff checklist does not call for flaps, in fact it specifically calls for flaps to be retracted. I have also watched a number of youtube videos of 421c takeoffs and have never seen a takeoff with flaps.

Of course if flaps help you in the simulator no harm using them I suppose.

Hope this helps,

Jesse

Edited January 23, 2022 by JesC

[fppilot 4,371]

12 hours ago, Vlad Tepes3 said:

Not even a 747 or A380 has a Vr of 198 Kts

Typo.  Meant to type in 98 kts per the Carenado F406 documentation.  My bad for not noticing my typo...

Edited January 23, 2022 by fppilot

[oldngray 8]

Thanks so much for the comments, Kind of felt it had to be my installation as I had searched here and elsewhere for bug speeds, flap and trim settings for this airplane without success but also felt it should fly off the runway at less than 120kts. with trim set at or near 0.

Since installing I noticed how difficult it was to get it airbourne and then had to get hard on the nose down trim to keep it from stalling.

This is what I have tried, T/O trim as much as 6.0 nose up (no joy), flap settings 1 and 2, (nope), attempt to relocate CG aft (no).

P3dv4, PAMR, rnwy 25, Gross weight 7416 Trim 1.0 nose up Flaps 1, Tried to Rotate at 100 kts, full rear deflection of yoke was finally able to get airbourne at 130 kts. BTW the way I loaded the A/C- Pilot and copilot 190 each, 3rd row 300 lbs each side (fat guys)  cab A 400 and B 100. This trying to get the cg rearward.

Think I will reinstall and see what happens, 

[oldngray 8]

Complete reinstall fixed everything. RC4 and GTN750 installed and working nicely. 

Will be more careful making changes in the future.  😬

Thanks 

[Ray Proudfoot 8,957]

On 1/23/2022 at 4:06 AM, Vlad Tepes3 said:

Not even a 747 or A380 has a Vr of 198 Kts at max t.o. weight.

Concorde had a Vr speed of 194kts with 90,000Kg of fuel and 100 pax when flying London - JFK.

No flaps of course. Just full power plus reheat! 😁

[LRBS 948]

Still short 4 KTS. 😂

Yep, it was a very nice airplane.