Project Tupolev Team :: View topic

Bell · ÊÂÑ

Hi,

track isn't good. Do you control latteral distance in turn by using NVU?

Generally, t/o was good. Just keep vertical speed 1-3 mps instead of 5-6 mps at the heights of 120-170 meters. Thus you'll avoid high values of G-force in turn.

Did you perform this T/O at nominal thrust? Based on acceleration above 170 meters and N2 RPM equal to 94% I assume it was T/O thrust on v2.03, but nor sure. Just set thurst more precisely since the 1% thrust gives extra drag for this exercise.

In crosswind turn the constant bank of 20* will be fine. Initially you had 33* (that exceeds the limit) and then reduced it to 15-18*. That's why the track width isn't good.

High flare at 20 meters. Need 6. Ballooning caused by high flare and hard touchdown.

Level flight and flight on G/S were fine!

WalterLeo · ÊÂÑ

Bell

Conditions as ever, T.O. power setting around 93 %

Regards

Walter

Bell · ÊÂÑ

The track log is much better, missed interception of the final course a little (due to hight IAS in turn, it was 410 km/h instead of 380) but generally it is fine.

Early flaps retraction from 28* position at 324 km/h.

Other components of the "cobra" are fine. Just reduce G-foce a little by several short yoke movements instead of one long movement when increasing pitch or trying to catch height for the level flight.

Lost Vref a little after full flaps extension.

Hard touchdown and further ballooning caused by the late set of idle thrust (idle was set after first touchdown but not at 4-6 meters).

Still wait for your final attempt for this exercise. Õèòðûé

WalterLeo · ÊÂÑ

Tu 154 M V. 2.03 w

15 deg C QFE 759

to 77,05 to 26,7 landing 76,8 MAC 26,5

Regards

Walter

maxmik · ÊÂÑ

WalterLeo, Bell

Sorry for interference, but I just wanted shortly comment on TOW.
It is extremely difficult to meet very strict conditions (G-force, speed, altitude) of the 1st exercise with such a small TOW of 77 tons in this conditions. Even for Tu-154B-2 77 tons are too light. I would suggest to take 81-82 tons which will still make landing possible although with maximum allowed landing weight of 80 tons.

Sorry once again and best of luck to Walter!

Cheers,
Max

WalterLeo · ÊÂÑ

maxmik
Bell

Hi!

Thanks Max to come to a point, which bothers me a little especially since using version 2.03. The conditions put where developed for the B2, in ver 2.02 of the M there was more power, but the other reactions in flightdynamics seemed similar to B2.
Âîïðîñ

But now with ver 2.03 especially with the new slower reactions of the engines (longer spool up and spool down time) the power reduction after passing 400 m lasts too long, you end up with a much too high climbrate or speed in the first and second turn overshooting altitude of 600 m and trackwith very easily.
Same happens at landing: Flaring and pulling back the power at 6 m results in idle-thrust at 1 meter and often after the first (hard) touchdown, even if your final descent-rate (before flare) is less than 4m/sec.

Next time I will try to start with 82 to (at engine-start). This means that I will take off with 81 to and land with 80 to (or a little bit more) and start power reduction on T.O around 350 m. On landing chopping the power at 15 m should result in idle-thrust at 6 m.

And: Refill the tanks for every circuit.

Óëûáêà

Regards

Walter

WalterLeo · ÊÂÑ

Now with 81,8 to before startup, T.O.: 81,3 to 27,4 % Landing 80 to 27,2 to,

QFE 759, 15 deg C.

Missed the intial earlier thrust reduction, overshot altitude.

Here the MSRP. positive G-loads remarkable less! Speed better under control.

Regards

Walter Óëûáêà

Bell · ÊÂÑ

Hi,

track width from 7,9 to 6,3 km. Make it better.

Flaps were shifted from 28* at 323 km/h. Wait for 340 km/h indication on IAS gauge and that definitely will give more than 330 km/h. I think this mistake caused by small resolution of the gauge on the monitor screen.

A couple of other mistake about late thrust reducing and overshoting the altitude you indicated yourself.

Also you lost the speed on final when flaps to 28* position were extended.

Hard touchdown due to late idle thrust at 1,5 meters and short pulling the control column.

Other is very-very good.

WalterLeo · ÊÂÑ

In this flight due to mishandling of the gear plaese check only the landing.

T.O. 81,2 to Landing 80 To Mac 27,2 27,0, Temp 15 deg QFE 159.

According to MSRP

at 15:16:42 I chopped the power (81,2%) Fuel burn 3 to at 11,6 m QFE.
at 15:16:43 I move the column back for flare at 8 m
at 15:16:45 Fuelburn was back to 1 to N2 72,2 % at 3,8 m QFE
at 15:16:45 Max ALFA 7,15 reached 3,8 m QFE speed 240
at 15:16:48 Touch down G 1,12 N2 66,6 % speed 235 Nose up ca. 4 deg

I was a little slow (255 km/h instead 265 and 82% power?), but what I wanted to try out was, that chopping the power you need 6 seconds that in ver. 2.03 Zero-thrust is reached due to the (realistic) slower spool down of the engines.

Awaiting your comments

Regards

Walter

Bell · ÊÂÑ

1. 12 meters for chopping power is too high. Need 6-4 meters. I prefer to set idle power after pulled back the control column.
2. Vref was 10 km/h lower than required.
3. The balanced elevator position was about 9,5* due to item above (max balanced elevator position on GS is 10* since values above 10* could reduce an effectiveness of elevator on flare. ).
4. Vertical speed was unstable until flare (non-balanced flight on GS).

The landing for the conditions mentioned above was not bad. But for better landing (and for passing all exercises) you have to fix all discrepancies above on descent and flare stages. Õèòðûé

WalterLeo · ÊÂÑ

Bell · ÊÂÑ

Sorry, may be I've translated this part incorrectly. When we say in Russian "to set idle thrust" this means we dispose the throttle for idle thrust but it does not mean the moment when the idle thrust occured.
Therefore it's required to dispose the throttle for idle thrust at 6-4 meters.

Hold off in your previous flights caused by high flare (15-20 meters) or late throttle disposal (at 2 meters, for instance).

Also, the balanced elevator position, CG, Vref influence on the range for pulling the column on flare. To avoid hold off, try to get accustomed to your persomal yoke pulling range in case all parameters above are fine on GS and flare+throttle disposal done at 6-4 meters.

WalterLeo · ÊÂÑ

Hi Bell:

After some tries I went back to ver. 2.02w

To: 81 to Mac 27,3 Landing 80 to Mac 27,1

QFE 759 15 deg C.

I handle the throtteles with NUMPAD 9/3. Ver. 2.03 moves much slower the throttles.

The lower limit of elevator travel in ver. 2.03 gives me the feeling of overcontrolling and slower trim-reaction.
In general I have a much better feeling with ver. 2.02 for this exercise.
There were still excursions on altitude and speed.

Here the MSRP, awaiting your comments,

best greetings

Walter

Bell · ÊÂÑ

Maximum speed you can accelerate to in this exercise is 450 km/h. You had 430. It would be better if you accelerate up to 450 having lower pitch but you will not get G-force values more than 1,2 and lower 0,8 in that case, and will not overshot the level height. But generally take-off and climb were fine.

Start turning close to 200 meters, you've done it at 250.

Use MET after rotation. It also relates on G-force.

Track is perfect, but its width is 7 km. Need 8.

Other stages were very perfect Âîñêëèöàíèå

Approach on GS and landing are excellent as well. You've done all properly like its written in manual. Õîðîøî

Mistakes highlighted with bold do not allow me to pass you for the next exercise. Fix them, please.

WalterLeo · ÊÂÑ