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Power / speed issues

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tdumontelle View Drop Down
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    Posted: 30 Apr 2017 at 6:40pm
Excited to fly this great looking product. Updated to SP2 and I'm having a few issues:

Following the flight tutorial guidelines, I go through engine start. I'm loaded with default passengers and about 80% fuel load.

1. When the engines start the RPMs go to maximum and stay there, also the EGT goes to the red and stays there. After 5 minutes both engines eventually fall back on RPM's and EGT goes down.

2. Take-off seems sluggish. Pulling back on the stick at 110 knots, aircraft but no rotation until 140-150 and then only 500fpm. Gear up and flap clean up improves.

3. Climb out; with RPM's set to 14200 if I try to trim for 150-160knots I end up in a 15 degree pitch up climb. EGT was in the yellow through climb.

4. Cruise. At 15000 feet I can't seem to even get 1400 rpms. Speed is at 240 KIAS or higher at max. AT 220 KIAS fuel flow seems to be at around 800-1000 pph.

5. Approach to landing, the aircraft doesn't want to fly level at 120 with the recommended flap setting.


I think I'm missing something with the fuel trim or something else with the start up that may not be in the manual.

Any help is greatly appreciated!

T

Also, I purchased this right before SP2, so never actually flew except SP2
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keithb77 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote keithb77 Quote  Post ReplyReply Direct Link To This Post Posted: 01 May 2017 at 4:43pm
SP2 was updated many times - do you have the 1.06 download?
Cheers
Keith
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tdumontelle View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote tdumontelle Quote  Post ReplyReply Direct Link To This Post Posted: 02 May 2017 at 11:41pm
I'm not sure. I downloaded it on 04/30/17 I think. Where can you find the version number?

I found a work around for the high rpms at start. I have the fuel cocks shut off and then hit the starter. After it revs up a bit I open the fuel up. Similar to how I start a B1900 or C208.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote tdumontelle Quote  Post ReplyReply Direct Link To This Post Posted: 06 May 2017 at 7:28pm
Ok, did a full reload and made sure it was 1.06. This fixed the startup issue with no sticking high rpms. Rotation is still well after 120knots, climb at 14200 rpms is still at like 16 degrees pitch to maintain 160 - 180 knots. Didn't even try to descend or land. I don't know if there are still problems with the FDE or flight model or if I'm missing some step that's not in the manual. Almost wonder if the airspeed indicator is off or maybe its supposed to be MPH instead of KIA.
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tdumontelle View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote tdumontelle Quote  Post ReplyReply Direct Link To This Post Posted: 23 Jul 2017 at 5:53pm
I did file a ticket on this. They referred it to the developer. Has anyone found some work-arounds for these? I also followed up today to see if there was an update coming out.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Uncle Bucc Quote  Post ReplyReply Direct Link To This Post Posted: 16 Aug 2017 at 1:27pm
I too have recently had this problem and the aircraft won't take off from the runway.

I haven't flown her for quite a while and I have upgraded my flight control systems, rudder pedals etc rather than the "all in one" sticks that are out there.

I just fancied a change and after three days feel lost for ideas.

I also appear to have trouble getting everything to link to the specific profile type using FSUIPC.  Checked their forums nothing there to help with this problem.

But I shall persevere.  Just fancy doing the Anchorage to Cold Harbour flights that were in an issue of PC Pilot.

Happy to read what possible solutions get posted.

EDIT:  Fixed.  FSUIPC has recently been updated plus I was using an earlier version of the a/c.  All now seems fine as I just did a small flight from EGCC to EGNT no problem. 
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thorsten42 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote thorsten42 Quote  Post ReplyReply Direct Link To This Post Posted: 01 Sep 2017 at 9:55am
Hi all,

I just installed the latest 2.01 version into my p3d v4 and I'm getting the same speed problem as described. Afaik I never had it before in FSX or P3D v3 with older installs. As the Fokker is doing nicely with the same engines it has to be something with the 748... any further ideas?

Cheers
Thorsten


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Tobus View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Tobus Quote  Post ReplyReply Direct Link To This Post Posted: 01 Sep 2017 at 10:47am
I'm experiencing the exact same thing as Thorsten42 describes in FSX:SE, with the news SP201 installer.
Fokker behaves like a sportscar and 748 as a tractor with same engines and general characteristics.
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almerejo View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote almerejo Quote  Post ReplyReply Direct Link To This Post Posted: 01 Sep 2017 at 1:37pm
Updated to the latest version, and not had any issues both with the power or take off speed issues.

However, I do find as it loads in it's 'powered-up, ready to roll' mode, it behaves like a wild bronco ready to break free and gallop away, as I have to keep applying brakes to slow her in the taxi to the take-off runway.

So, switched to the C&D Tutorial, and therein I was able to control the taxi speed. However, when calling for full power and take-off speed, there was no issue.

After spending a great deal of time in the 737NGX, this aircraft makes a lovely change. Did d long flight TNCA to TNCM with it.

Only wish I could get GSX to interact with it a bit better, i.e. catering, fuel. Push-back works fine.
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thorsten42 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote thorsten42 Quote  Post ReplyReply Direct Link To This Post Posted: 05 Sep 2017 at 11:47am
Anybody else experiencing this behaviour? Nice to hear that your install is working almerejo but that doesn't help the other users experiencing the observed behaviour. I just did another start attempt following exactly the documented steps in the tutorial flight but the 748 is def not taking off as expected. Way to slow and even with the trim of +3 not rotating below 120 knots. It feels like flying on one engine and towing an anchor...

Cheers
Thorsten
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almerejo View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote almerejo Quote  Post ReplyReply Direct Link To This Post Posted: 05 Sep 2017 at 12:41pm
Check that both HPC levers are fully forward since you mention that it feels like it is trying to take off on one engine, it may be that one of the engines is not fully receiving fuel via that HPC lever. Also check the gust locks are not engaged.

I was basically trying to point out there is nothing fundamentally wrong with this aircraft as she stands in the current version.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote thorsten42 Quote  Post ReplyReply Direct Link To This Post Posted: 06 Sep 2017 at 6:57am
In several users opinion there is indeed something fundamentally wrong with this airplane. As stated before I followed exactly the checklists and I know the 748 quite well. I've flown Rick Pipers freeware version for several years and with some given respect it had a lot more system depth to be followed exactly than this recent AH Version including working fuel trim etc... But thats not the point here. We all know what AH planes stand for and they are nice for some relaxed fire and forget flights if you are tired from watching systems in other planes. (even if we know that other releases like the Viscount never reached a state that would be called flyable in all stages ;) ) For the HS I did some further testing and research...

What indeed puzzles me a bit is that both the Fokker F27 and the HS748 are meant to provide a somehow compareable behaviour taking into account the engines used and the fact that they were direct competitors. Some sources tell us for the HS748 that for example:

[...]This aircraft has a takeoff run of only 2,750 feet, for STOL performance it has a long-span wing, mounted low, with Fowler flaps driven by an electric actuator. The Rolls-Royce Dart turboprops, mounted with their jet pipes above the wings, are rated at about 2,280 hp, though some military versions have 3,200-hp Darts. Most civil versions of the HS 748 seat 40 to 58 passengers and some are equipped for freight or passenger/freight operations.[...]

Other sources like https://www.skybrary.aero giving us for both the Fokker and the HS748 regular required runway lengths for takeoff of about 1200m (roughly 4000 feet).

The Fokker seems to be a way overpowered then and easily reaches the STOL performance mentioned for the HS. On the other hand the HS doesn't meet the lets say normal figures of 1200m anymore since the last few versions. And for the STOL it would need rocket booster ;)

I found a few old installers on my disk and did some tests in my p3d v3 install. Installer marked with SP1 used and the take off performance was what I would expect to match the 1200m runway length. But miles away from the STOL performance. Next try was with installer marked 1.06 and the FDE seems to be way off. Same with the latest 2.01.

So honestly I don't think that me or the other users seeing the take off behavior are doing something fundamentally wrong.
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almerejo View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote almerejo Quote  Post ReplyReply Direct Link To This Post Posted: 06 Sep 2017 at 8:35am
Ah, Rick Piper's 748. Now, that certainly evokes memories. Pity it never got developed further. Would have been an instant buy for me in P3Dv4.

And I bow to your superior knowledge of this particular aircraft. And I was not specifically saying that there was not anything fundamentally wrong to each and every simmer's purchase. What I meant to say was that in my instance, I basically found nothing fundamentally wrong. I was able to take-off from short runways, able to power up to a climb and then cruise for quite a long flight(LEPA-GCLP) and it fulfilled, for me, all the parameters of that Tutorial.

I would not go as far as to say it is a totally flawless state-of-the-art FS add-on. Far from it.

I just hope that JF look at yours and others issues with it and come up with a SP to resolve it and/or embrace some of Rick Piper's excellent model.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote thorsten42 Quote  Post ReplyReply Direct Link To This Post Posted: 06 Sep 2017 at 8:39am
Thx almerejo... yeah lets hope that we'll find whats causing the issue. One question... what runway length is the shortest you get the HS up in the air? Just for comparison. Me not getting it safe into the air below 1300m / 4400feet with v2.01 and 1100m with the older installers.
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almerejo View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote almerejo Quote  Post ReplyReply Direct Link To This Post Posted: 06 Sep 2017 at 9:11am
I'll check that out next flight and update accordingly.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote almerejo Quote  Post ReplyReply Direct Link To This Post Posted: 06 Sep 2017 at 5:39pm
Okay, just made a test flight and I can now confirm this aircraft struggles with 100% fuel to climb off a 1420m runway. She just about makes it.

I have been using her on normal mainstream airports rather than S/TOL runways, which is why I had no power and climb issues.
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tdumontelle View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote tdumontelle Quote  Post ReplyReply Direct Link To This Post Posted: 06 Sep 2017 at 9:44pm
I sent an email in regards to my original support ticket. I asked them if they were working on a solution or if they just notified the designer of the problem. I haven't had a response yet.

I really like the aircraft, and I'm excited to fly it, but its frustrating to have a STOL aircraft that can't STOL. I had the freeware version mentioned above and it was cool so I paid money to get a more refined version. Seems like since it did seem to work in a previous release that a solution wouldn't be too far off. I think I filed the ticket in early May or so.

    
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Post Options Post Options   Thanks (0) Thanks(0)   Quote snave Quote  Post ReplyReply Direct Link To This Post Posted: 07 Sep 2017 at 5:45pm
Provide take off weight and weather conditions or there is no basis for comparison. 

Assuming the fuel trim is correctly set (and is actually working in the latest version) you may well struggle to climb off a 1420m runway.

STOL means `short` by the standards of jets of the day.  LOL
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thorsten42 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote thorsten42 Quote  Post ReplyReply Direct Link To This Post Posted: 08 Sep 2017 at 6:30am
Snave you're absolutely right. I'm using always default fair weather with null wind and standard barometric pressure for test flights with airports near sea level. BUT indeed I was not checking the weight. The fuel trim is not simulated and per manual stays at zero (thats not nice regarding system depth but expected). The only source I found was that the HS was capable of takeoff runs around 2700 feet but not mentioning fuel and load. I've rechecked and yes with default load and reduced fuel (35000lbs actual weight with max gross at 46500lbs) it is indeed capable of taking off around 2700 feet. Nothing more to say than sorry, my fault. I did not follow my own level of professionalism that I expect from others. With the latest tests I would say it acts like the available numbers tell us as far as I can judge.

Cheers
Thorsten
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almerejo View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote almerejo Quote  Post ReplyReply Direct Link To This Post Posted: 08 Sep 2017 at 8:21am
To add to this, I did qualify my last post by stating '100% fuel', the following post from Snave balances out.

Nevertheless, a great thread with salient observations.
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