Boeing Flying Help

#1BlueCadwalPosted 12/1/2008 6:25:50 PM
I was just wanting to fly from MIA (Miami International) to OIA (Orlando International) since it is supposed to be only about a 30 minute flight. I took a high altitude route and set my auto pilot for the correct heading at an Altitude of 15,000 feet. The next thing I knew my airplane was flying straight up and stalled, I pulled it out of a death roll before hitting the ground, but I couldn't figure out what caused the plane to stall in the first place.

I repeated the conditions and the same exact thing happened.

I used both the Boeing 787 and 747 for the flight between the hours of 3pm and 6pm (daylight - sunset). The only thing I can think of is upper atmosphere conditions were less than optimal for flying, but I figured I'd run the conditions past the forum since it seems weird that 4 flights end with the same result.

I was finally successful in flying the same exact route at 16,000 feet on the LJ-45. The failure to fly is not a result of my inexperience with the Boeings. Although I'm new to the game, I was able to successfully fly from Chicago to New York 2 times over the weekend.
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"Darn the conservatives, full speed ahead!" -BlueTruth
"What's next? Ubisoft hates Nintendo?" -Linkman25
#2Human_FlawPosted 12/1/2008 10:48:32 PM

BlueCadwal posted...
I was just wanting to fly from MIA (Miami International) to OIA (Orlando International) since it is supposed to be only about a 30 minute flight. I took a high altitude route and set my auto pilot for the correct heading at an Altitude of 15,000 feet. The next thing I knew my airplane was flying straight up and stalled, I pulled it out of a death roll before hitting the ground, but I couldn't figure out what caused the plane to stall in the first place.

First, I assume you were flying the default Boeings (737, 747) and not a payware, or freeware addon, correct?

If this is the case... The first thing that comes to mind is you might have had your flaps set too high (down) and this can create tremendous lift given the right conditions (V speed + N1/TOGA settings). The standard rule of thumb for the 737 is takeoff flaps should be set at 5 degrees. The 747 should be at 20 degrees (this is what I meant about having them set too low; the 747 lifts right off the ground with very little throttle and short runway length with flaps at 20).

The second thing that has to do with the flaps is the TOGA (Take Off/Go Around) function built into Flight Simulator. If you aren't careful, this can catch a lot of new pilots off-guard because it simulates the increased thrust used when taking off, or for rejected landings. New pilots aren't prepared for how much force TOGA provides and using my example of the 747, before they know it they are off the ground and pointing skyward at a dangerously steep angle of attack because the nose keeps rising as they climb.

However, there is a safeguard built-in for the TOGA, but it is only present if you turn on the FD (Flight Director) switch. It is supposed to guide a pilot's rate of climb (angle of attack) by giving them a point of reference to follow. In Boeings, it is usually in the form of the cross bar of the crosshairs hovering between the 10 and 15 degree mark on the electronic attitude indicator prior to takeoff and during climb. A lot of new pilots don't notice the TOGA director because they aren't used to doing an instrument scan and are instead concentrating on looking out the virtual glareshield and "eye balling" their rate of climb a lot of times... Or, they aren't even aware there is a TOGA guide that exists. 

As for simulated atmospheric conditions...

This may have played a role, but maybe not as much as you think? However, if you had real world weather updates on and it just happened to be severe winds and less than optimal flying conditions the possiblity exists you might have encountered a "perfect storm" scenario -- not literally flying into a storm; proverbially speaking -- And this is why you kept climbing too fast, rolled the nose over and stalled four times in a row?

Also, one last thing your post demonstrates more than anything...

Do you use real charts to plot your route? Or do you use the default FSX flight planner to give you a rough estimate of where to go?

I ask because the autopilot in FSX is very basic, and the default flight planner can sometimes generate routes the autopilot has trouble with during actual flight. This is why even when I do short hops I research the real routes, so not only do I use the appropriate speeds, e.g. below FL100 restricted to 250 KTs, but I make sure my aircraft is at the appropriate altitude it should be given the specific SID, or STAR route restrictions I am using.

You will find if you take the time and use real charts not only does it give you a more realistic flight experience, but you will be using real world concepts and basic navigation functions real pilots use.

For example, I am compiling a log of my favorite routes, short and long, that coincide with the real ones airlines use. I took the time to look up the real SID and STAR routes/airways as well as the different approach plates for the airports runways. I have all the waypoints (route) information, the approproate speed and the best altitude recommendations for each route segment all in an organized Excel Spreadsheet I have prinited out. The reason I took the time to do this is because once you move onto more payware addons like PMDG, or Wilco/Pilot in Command... You need these pieces of information to program the FMC/CDU that takes care of VNAV and LNAV.

Now, obviously, you don't have to go into as much work as I and other virtual pilots do. No one is forcing you to play the game a particular way. I just listed my own method because I feel it maximizes *my own* enjoyment of FSX, and it helps use FSX to the fullest considering what FSX is supposed to be: A desktop flight simulator :)

#3tim142jPosted 12/2/2008 6:37:35 AM

BlueCadwal posted...
The only thing I can think of is upper atmosphere conditions were less than optimal for flying, but I figured I'd run the conditions past the forum since it seems weird that 4 flights end with the same result.

I was finally successful in flying the same exact route at 16,000 feet on the LJ-45. The failure to fly is not a result of my inexperience with the Boeings.


I big Boeing jet can fly in Florida at 15,000 feet usually with no problems. Not to be condescending, but it seems that you may not fully grasp the concepts involved in creating a smooth flight... are you using trim? Are you setting your engines to the right thrust? Are you maintaining an appropriate climbing angle of attack?

The ONLY reason an airplane stalls is because it exceeds its' critical angle of attack. That's why it's crucial for pilots to have complete control of the airplane, monitoring it's attitude and keeping them within the airplane's limits.. Weather does not directly cause an airplane to stall. An indirect reason may be an increase in stalling speed due to ice on the airplane, or an extreme tailwind gust, but all of those factors relate back to the fact that the critical angle of attack is being exceeded.

Long story short: DON'T CLIMB SO STEEPLY!

#4BlueCadwal(Topic Creator)Posted 12/2/2008 2:12:52 PM
Thanks Tim for taking my quote out of context and attacking the newb when he's sincerely trying to figure out what he did wrong.

"Although I'm new to the game, I was able to successfully fly from Chicago to New York 2 times over the weekend."

Obviously I know how to get a 747 into the air and make it from one location to another... SAFELY.

I never take a steep altitude climb because I fear heights. I don't put my flaps down while in flight due to the additional wind resistance they create at the time because that would've created wind resistance. The slow ascension allows my mind to adjust to the height.

When the planes became unstable, I was already at 15,000 feet and had been flying safely at that altitude for about 5 minutes before setting the autopilot. I set the height to 15,000 feet as well as the proper heading for where I wanted to go.
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"Darn the conservatives, full speed ahead!" -BlueTruth
"What's next? Ubisoft hates Nintendo?" -Linkman25
#5FrithPosted 12/2/2008 2:31:39 PM
It sounds like you were underspeed. The AP was pitching you up in an attempt to maintain lift, which in turn decreased your airspeed, necessitating additional lift...

What was your cruising airspeed? Are you set to view indicated airspeed or true airspeed?
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Stoe Orkeo!
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#6tim142jPosted 12/2/2008 2:34:19 PM

Don't be so defensive! No one is trying to attack you. I quoted the two lines that I thought you needed clarification on, then I gave you advice on why you may have fallen out of the sky in FSX...

That's all well and good that you were able to maintain an altitude, but you are missing several things that are crucial to maintaining and altitude and proper airspeed. You need to maintain an appropriate speed during cruise, and trim the plane to maintain level flight. Your autopilot does all this for you (including airspeed) if it is set and monitored, that's all!

#7Human_FlawPosted 12/2/2008 3:04:16 PM
BlueCadwal posted...
I was already at 15,000 feet and had been flying safely at that altitude for about 5 minutes before setting the autopilot.



Did you arm (activate) the autothrottle and set it to an appropriate speed, too?

Speaking generally, the proper procedure for both the real world and FS commercial airliners is to set your MCP (Mode Control Panel) settings BEFORE you takeoff. This way, all you have to do is engage the autopilot at the appropriate time and altitude (see below).

From what you posted, my guess is you were probably climbing at a steady rate, but didn't notice it because the aircraft appeared to be level from your POV. When you activated the autopilot, you probably didn't arm the autothrust, and/or set an appropriate speed for your given altitude. As other posters have stated, it appears there might not have been enough thrust (speed) to maintain the altitude and eventually the autopilot overcompensated by pitching (rolling) the nose to maintain the altitude and this caused a stall.

I don't mean to harp on this, but this is why using real life procedures and background information (SID/STAR airway charts) can help virtual pilots avoid problems like the one you encountered. It isn't just a "I am a newb to FS and am making mistakes" problem. Yes, that might be a physical part of it, but it might also be a symptom of a much larger problem and that is not taking the time to research what this software (FS) is trying to simulate and what the basic operating procedures and "rules" are to maximize what you get out of it (smooth, error-free flights), too.

Basically, for your next flight try this:

-Research the real route you want to fly
-Download (print out) the appropriate charts
-PLAN (write down) the way points and altitude restrictions
-Set your MCP (speed, crz alt, heading) before you take off
-Engage the autopilot shortly after takeoff The last part (Engage the autopilot shortly after takeoff) is probably the area you should concentrate on because while FS is all about flight... The problem you encountered sounds like it could have been avoided all together with just some basic planning like I outlined above. If you set the MCP set before you leave the ground, I guarantee you you'll never stall out again, or encounter other severe anomalies like the one you encountered barring any malfunctions in FS, the autopilot and or your own PC hardware.
#8Human_FlawPosted 12/2/2008 10:14:54 PM

Update:

I flew the city pair you flew (KMIA to KMCO) in both the default 737, and Wilco/PIC 737-300. My cruise altitude was 15,000FT. Both of my flights were error free. I even used real world whether.

This is the route I used:

HEDLY.PHK.GOOFY5

Here is the full route:

Human_Flaw posted...

KMIA

HEDLY

PHK

BAIRN

ODDEL

SABOT

KMCO

The SID for KMIA is HEDLY. The STAR for KMCO is GOOFY5. The transition is PHK (Pahokee). The FMC (in the Wilco 737) calculated everything properly and the only adjusment I had to make was one altitude/speed restriction that was slightly too fast for the altitude (270KTs @ 9000FT). The altitudes calculated by the FMC were also consistent with the charts I used to fly your particular route, so I did not expect any problems as far altitude, pitch and thrust were concerned.

The only thing that might have screwed you up was you might have encountered a MICROBURST and that is something that can crash a plane (in the real world). If you had real world weather on, you *might* have donwnloaded one... But I am not even sure FS can simulate microburst conditions. This is the only other thing I can think of that might have screwed you up...