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My default CRJ700 flies with a nose-down attitude


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Hello.

My default (FSX Steam) CRJ700 and the Airbus A321 fly with a nose-down attitude,

Is this normal ?

If not, how can it be rectified ?

 

Other default aircraft (eg B737-800) fly normally (horizontal)

 

Many thanks

 

Kind regards

 

Frank C

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Frank - Read below, Similar Threads, the one submitted by Double J! Once you read it, you will realize that you might have stirred up the "hornets nest" of conversation relating to this! I haven't seen pics of your aircraft, so I/we can't tell, but I think it all comes down to how your eyes perceive what you see when you look at the aircraft in flight? Probably two people could look at the same image, one might think it's level and the other swear that is "nose down!"

 

There could be something wrong with the 2 aircraft, but nobody can tell until you share a pic of what you are seeing!

 

Good luck - Rick

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Hello Rick

 

Thank you for getting back to me.

The flaps are fully retracted (I am a real-time pilot so this would be very basic to me).

Only the aforementioned two aircraft fly nose down. I can pause the said aircraft over the sea with the horizon as a guide and it shows clearly the nose-down attitude. Then I change to any other default aircraft (still paused) and new substituted aircraft will line up perfectly with the horizon.

It does not bother me too much....just doesn't look right!

I will post a snapshot in the next few days

 

Many thanks for you time.

 

Kind regards

Frank

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Hello Rick

 

Thank you for getting back to me.

The flaps are fully retracted (I am a real-time pilot so this would be very basic to me).

Only the aforementioned two aircraft fly nose down. I can pause the said aircraft over the sea with the horizon as a guide and it shows clearly the nose-down attitude. Then I change to any other default aircraft (still paused) and new substituted aircraft will line up perfectly with the horizon.

It does not bother me too much....just doesn't look right!

I will post a snapshot in the next few days

 

Many thanks for you time.

 

Kind regards

Frank

 

Thanks, Frank! I think everyone would like to look at a screenshot, as this topic has come up before. I'm very curious, as my CRJ700 and A321's are 2 of my favorite aircraft and I have plenty that I have collected. Both these aircraft have never seemed like they fly nose down, that's why I would like to see a pic! We all look forward to looking at the pic! If they are truly abnormal, there are some very seasoned veterans on here, some were even involved in the past topic discussions!

 

Thanks Frank and have a nice evening! - Rick

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Hi Rick

The CRJ700 and A321 are my only two which fly in this nose-down attitude. The B737 is just an example of aircraft flying horizontally.

All three aircraft were set to 400 kt Indicated and at the same location/

 

 

A321.jpgCRJ700.jpgB737.jpg

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Have you tried messing with the fuel and payload menu, shifting weight rearward?

 

I haven't, but it seemed logical.

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Hi Rick

The CRJ700 and A321 are my only two which fly in this nose-down attitude. The B737 is just an example of aircraft flying horizontally.

All three aircraft were set to 400 kt Indicated and at the same location/

 

Frank - I don't know what to say, I tried just a few minutes ago, took the CRJ700 to 25,000 feet and tried 2 different airspeeds:

 

310 KIAS - 456 knots ground speed

 

380 KIAS - 537 knots ground speed. Note: I never got to the 400 KIAS that you used. The overspeed warning alarm started around 340 - 350 KIAS, it got to 380 and didn't move from there, at least I wasn't going to wait on it!

 

I did take screenshots and both looked slightly nose down, but it was so negligible that I didn't even bother posting here, but I did save them.

 

My question and I tend to agree with il88pp, why would you chose to fly the CRJ700 at 400 KIAS? 310 KIAS was producing a 456 knot ground speed (and I didn't have to listen to the overspeed warning). I didn't see it with my aircraft, but I can clearly see the nose down with your screenshots, but I do think that this 400 KIAS airspeed would contribute to the nose down attitude you are getting. I'm going to sit back and see what others say, others that have the expertise to say what is, what should be and explain the difference between the two!

 

I really hope you find an answer. Like I said, I read earlier today where this topic has come up before!

 

Anyway, I will be watching, because now I am interested in knowing. Have a nice day! - Rick

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Hello folks

 

Following on from your advice I have just flown the CRJ700 and A321 at 300 kts Indicated and they both still fly with a nose-down attitude. The other aircraft all fly horizontally.

 

I have not tried moving the payload but will give that a go later today.

As for fuel, I have it set to unlimited.

 

Kind regards

 

Frank C

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Hello again everyone

 

I have been taking in the advice and experimenting, flying the CRJ700 from 300 indicated, gradually taking off the throttles and the nose-down attitude gradually levelled out between 260 - 250 indicated.

 

I only flew at 3,000' with the weather custom set to clear skies and no wind.

 

Kind regards

 

Frank C

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This is in response to user DownWind66's questions.

-------------

 

When the air moves faster over the wings, the result is more lift.

The consequence is that to stay at the same altitude, the plane requires less pitch up. (pitching up results in more lift. pitching down in less.)

 

When increasing speed, if you don't reduce the pitch, the plane would climb.

Ways to pitch down would be:

-1- push the joystick forward/yoke in, and hold it there from then on.

-2- trim down the elevator.

(In manual flight you would use the yoke while accelerating. And when the new higher speed is reached, you would start adding trim while at the same time bringing the toke/joystick back to the neutral position.)

 

-or, -3- you let the autopilot keep you at the same altitude. The autopilot only uses the elevator trim to pitch down. It does not use the yoke.

 

-----

The net result:

increasing the speed while you stick to the same altitude, the pitch of the aircraft will reduce. Sometimes even going to negative pitch.

 

----------

All these planes, the 737, a321, crj700, and 747

have a maximum airspeed of around 345 knots.

The maximum airspeed is the highest speed a plane can safely reach. Fly faster, and the plane will start to break apart.

It is a limit you should not exceed. (it is possible to fly too fast and have your plane fall apart. Be careful.)

The limit for each plane can be found in the information pages on the kneeboard. The kneeboard can be viewed while you are flying in fsx.

 

Why not exceed it? long story.

Action = - reaction.

If you bump into a wall at 10 Mph, it hurts. If the wall bumps into you at 10 knots, it hurts the same.

Let's say it's a calm day, no wind. No air movement.

Let's say your fly at 300Kt. the air may be standing still, but you are hitting it at 300 kt.

So if you would stick your hand out the window, you would feel the rushing past. At 300Kt.

With your hand sticking out a small hole like that, getting hit by air at 300Kt, your hand would get clean ripped of. The pressure the air exerts on your hand would be enormous.

 

This same pressure is experienced by every part of the plane. The windshield, the wings, the engines, the tail, everything. Also by the front facing pitot tubes.

This results in air pressure inside those front facing pitot tubes. This pitot tube air pressure is shown in your cockpit. As Airspeed. Indicated Airspeed. (you don't see 25 psi, you see 250 knots. [25 and 250 are not real world actual values, this is just as example.])

As I said. Indicated Airspeed. Also known as IAS.

 

This means that the IAS you see on your Cockpit gauges are a direct result of Air Pressure created by the wind hitting the plane.

If this wind speed gets too high, parts will start blowing off the aircraft. body panels rip of the top of the plane, the tail gets torn apart, all control is lost and the plane breaks up completely.

So keep IAS below Max Airspeed given in the kneeboard.

 

--

Weather.

Between a high and a low pressure weather area, you often have an area where two layers of air flow in opposite directions to each other. Not above each other, but next to each other.

Like so:

East

-high pressure area-->> South

West

 

In the west is a Low, with wind flowing Northward. And in the East is a High, with wind flowing South.

If you are flying from Southwest to Northeast, you will cross the line, and go from an area with maybe a 20 knot tailwind to an area with a maybe 25 knot headwind.

 

You might think there is a wide mixing area where wind is almost neutral. But this is not the case. Usually one air-layer has more moisture then the other. And is also colder. And air layers of different temperatures do not mix easily. So the transition from tailwind to headwind will be very abrupt. Very sudden.

 

Now why would that matter?

That matters because you are always flying in an air layer.

Let's say you have a 20 knot tailwind. your IAS is 300kt.

In other words the air-layer you are in is moving in the same direction you are traveling in. And you are going so fast that you still feel a 300 knot pressure on the windscreen.

 

So even though the wind is moving the air away from you, you are "overtaking" it with a speed that is 300knot faster then that wind is moving away from you.

Now the tailwind suddenly drops away. In other words "the air-layer around you no longer moves away from you".

The plane is a heavy thing, it doesn't stop on a dime, it has loads of momentum. So it keeps traveling forward at the same speed in relation to the ground.

But the air around the plane no longer move as. So now the air hits the windscreen of the plane with 20 knots more speed.

And the pitot tubes, the tail, the engines, and the wings.

pitot tubes: IAS will now of course indicate 20 knots more. 320 instead of 300

Wings: flying at 320 knots instead of 300 results in more lift.

Autopilot: trims down to stay at same altitude. Because the extra lift is making the plane pitch up and climb.

Throttles: will spool back to reduce speed back to the 300 that is still set on the autothrottle.

 

However, many of these systems are slow to respond. It takes some time to slow down. Autopilot responds relatively fast, but throttles take time to spool down, and the plane is simply so heavy it takes some time before it slows.

 

----------

That's just with a 20 knot tailwind dropping away.

But if the 20 knot tailwind is replaced by a headwind of 20 knots, the combined effect is an increase in IAS of 40 knots.

 

If at that time you are very close to maximum airspeed, you have a big problem.

One moment you are flying along at 340 knots, just 10 knots below max indicated airspeed, the next moment you are doing 380 knots, 30 knots above max airspeed.

 

You can't slow down by disengaging autopilot and pulling the yoke to pitch up quickly. Pulling up, the change in elevator position would put so much force on the elevator and tail construction it could easily shear off.

 

 

Conclusion/summary:

Know the maximum Indicated AirSpeed IAS of the plane you are flying.

Stay well below it.

Pitch will be lower at higher IAS. (in any given situation, not just in level flight.)

When checking the pitch on the PFD (Primary Flight Display) in the cockpit, if pitch looks abnormally low for the situation, check if your Indicated Air Speed is not too high.

Be aware wind shifts can occur. Tailwinds can turn to headwinds, increasing your IAS very suddenly.

 

 

 

----

last remarks

The allowed Maximum Indicated Airspeed is lower when the flaps are extended. There is a Max Flap Speed for every flap setting. (More flaps set--lower max speed allowed.)

There is also a speed limit for flying with landing gear extended.

And a speed limit above which you may not extend or retract the gear.

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##### il88pp ##### - You say "In response to Downwind66"s questions...." I had no questions of you or anyone else on this subject, connolly44 is the OP for this thread! I don't fly at these airspeeds or at high altitudes, and I have never had issues with either the CRJ700 or the A321. Not being disrespectful towards you, I am not reading your short story either, as my mind has enough in it without adding to it! Maybe, Frank, the OP has time to read it, I do not!

 

Rick

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Hello again everyone

 

I have been taking in the advice and experimenting, flying the CRJ700 from 300 indicated, gradually taking off the throttles and the nose-down attitude gradually levelled out between 260 - 250 indicated.

 

I only flew at 3,000' with the weather custom set to clear skies and no wind.

 

Kind regards

 

Frank C

 

Frank - Glad to hear that! Same results with the A321?

 

Have a nice day! - Rick

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Downwind66,

You said in your post you weren't sure Why increased speed would cause lower speed. So I set out to explain that to you.

I decided to stick on a lot of extra info.

Not because it was needed, but because it is good to have the whole story.

 

To fully understand, a simple "speed up means pitch goes down" is not enough. There needs to be (a lot of) context.

On when this happens, why this happens, and how it happens.

 

I do not see how you saw my text as criticism.

My text was only there to provide information. No criticism meant at all.

il.

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Sorry. I see I misread your post. You did indeed not (need to) ask.

 

Nevermind. As I already said, no criticism was intended.

 

Not a problem, and I did not take it as criticism, I just wanted to let you know who the person in need was and it wasn't me! I did, in fact, agree with you that 400 KIAS was about 100 knots too fast. The fastest speed I have set on either the CRJ700 and/or A321 is 310 KIAS, and have not had issues myself!

 

Thanks il !! Rick

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Hello folks

 

Following on from your advice I have just flown the CRJ700 and A321 at 300 kts Indicated and they both still fly with a nose-down attitude. The other aircraft all fly horizontally.

 

I have not tried moving the payload but will give that a go later today.

As for fuel, I have it set to unlimited.

 

Kind regards

 

Frank C

 

Some submarine movies always have the crew running forward when they need to make a fast dive to get away from the depth charges. :)

 

I though maybe moving passengers rearward would nose the plane up a bit, but it didn't seem to have much of a noticeable effect.

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I just did a flight with the CRJ700 from KSFO-KPSP. Cruise altitude was at FTL330, KIAS at280, MACH=.78 and Ground Speed of 502 Knots. It does show slightly nose-down. I am using A/P.

 

I found even sitting on the ground, the same nose-down angle.

 

CRJ700.JPG

Still thinking about a new flightsim only computer!  ✈️

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I just did a flight with the CRJ700 from KSFO-KPSP. Cruise altitude was at FTL330, KIAS at280, MACH=.78 and Ground Speed of 502 Knots. It does show slightly nose-down. I am using A/P.

 

I found even sitting on the ground, the same nose-down angle.

 

[ATTACH=CONFIG]203212[/ATTACH]

 

Tube-liners aren't my forte! However I have noticed more that one aircraft flies straight and level with a nose down attitude. The one that I really noticed RW was the B-52, (BUFF) which you might have heard of, in the 1960's.

 

During combat in Vietnam I saw several flights of BUFFS drop tons of bombs. To be honest, my first thought was this BUFF is going to crash!!:(:(

 

Thankfully I was reassured by people with much more experience watching B-52s (BUFFS) than mine at that time. The B-52 (BUFF) in normal straight and level flight appears to have a nose-down attitude. It's not about to crash. Nor is it losing altitude. That's just the how it looks while flying!

 

Does this apply to your concern? Since I haven't flown RW since 1968, I can't say. However, based upon my experiences not every plane in flight looks exactly as you have expected. ;)

 

Rupert

Being an old chopper guy I usually fly low and slow.
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Some submarine movies always have the crew running forward when they need to make a fast dive to get away from the depth charges. :)

 

I though maybe moving passengers rearward would nose the plane up a bit, but it didn't seem to have much of a noticeable effect.

 

I just love submarine movies and books. I would never ever want to serve on one though. Those guys just impress the heck outta me.

Stuck in a (relatively) small tube with the same guys for 6 months at a time would drive me buggy. Heck, I can't think of 10 people I could spend six months cooped up with. Not without going homicidal. That's why they impress me so much. They stay in that sub, and they don't try to kill one another. For six months!! IMPRESSIVE!!

 

Anywho, those movies that show the people all rushing forward to aid the dive are accurate. For the WWII subs, anyway. Moving the crew for'ard like that helped the sub pitch down faster, since their underwater speed wasn't very high, and thus the diving planes didn't have the authority you'd think. Getting underwater fast was a sub's only defense against surface ships. The war-ships were generally faster than the subs, and had alot more, and more potent, armament. All it would take would be 1 hole in the wrong place at it was all over for the sub. If the sub could sneak up on them unseen, fine, a couple torpedoes and a few 5" deck gun rounds and the surface ship was gone.

But that wasn't their main function. They were after any and all enemy cargo ships. THOSE hurt the enemy a lot more than loosing a war-ship did. The only time they'd hunt a war-ship is if it was for self-defense.

 

Another thing: They weren't trying to change the sub's AOA. They were changing it's overall balance. A plane flies at a specific AOA at it's nominal cruise altitude and airspeed. Moving the passengers to the rear won't change that. It'll fly at the same AOA, it just might need a little more trim to accomplish that.

Subs don't really HAVE an AOA the same way airplanes do. They are nominally kept on an even keel. They can go up, go down, turn, whatever, but they do it level. Generally.

As I said, on the WWII subs, during what they called a crash dive, they would trim it nose down, but to help that, the spare, or un-occupied crew would all rush forward to help. Remember, on a crash dive, they would have gone to General Quarters (battle stations) as soon as the necessity for the crash dive was perceived. Thus EVERYbody had an assigned station, but some weren't "in use" during the beginning of the process. The WWII subs didn't have an as effective, nor as sophisticated, a trim system that the modern, nuclear powered subs do. Once the boat began to level at depth, the crew would return to their assigned General Quarters stations, to help the COB (Chief Of the Boat) trim the boat back to level.

 

Planes may change attitude, but they cruise at a specific AOA. Moving weight around won't change that, although if you move the balance point too far from it's designed limits, you will have controllabilty problems. BIG ones. Subs don't have that problem to the extent planes do.

 

Sorry for babbling. Like I said, I just love subs, and have studied them a bit. Including reading a number of books written by sub commanders and crewmen.

Pat☺

 

PS: Michael, as I recall, the designator BUFF means Big Ugly Friendly ummmm...errr...FELLOW. Yeah, Fellow. That's it...

:p :rolleyes: ;)

Pat☺

[sIGPIC][/sIGPIC]

Had a thought...then there was the smell of something burning, and sparks, and then a big fire, and then the lights went out! I guess I better not do that again!

Sgt, USMC, 10 years proud service, Inactive reserve now :D

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You are correct, angle of attack in planes does not depend on where the cargo/passenger is. It does take a different trim setting.

(Too far back and you won't have enough trim available to keep the angle of attack correct, (and keep the plane airborne).)

 

I didn't post that last night. Couldn't find the right words. Impressed by that wonderfully clear explanation you gave there PhantomTweak. Just perfect.

Have a great day!

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PS: Michael, as I recall, the designator BUFF means Big Ugly Friendly ummmm...errr...FELLOW. Yeah, Fellow. That's it...

:p :rolleyes: ;)

Pat☺

 

Hey Pat, that's somewhat (not really) close. And that's the "handle" those who actually fly them chose. Think how that works out for the rest of us!!

 

Say hi to Ms. Ghost as well!!

 

Michael

Being an old chopper guy I usually fly low and slow.
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The lovely Ms. Ghost says "HI" back :cool:

 

She wanted you to know, we were thinking of you on Derby Day. Were you there? Make a small fortune on the race? It was a great race, btw :D

 

I am familiar with the BUFF acronym, but this being a family-type forum, I figured Fellow was a better choice of word than the actual one. I may be a former Marine, but I have that much control, at least ;)

 

Have fun, man!

Pat☺

[sIGPIC][/sIGPIC]

Had a thought...then there was the smell of something burning, and sparks, and then a big fire, and then the lights went out! I guess I better not do that again!

Sgt, USMC, 10 years proud service, Inactive reserve now :D

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