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Nick Dobda

737 down

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Had my first major crash tonight, no survivors.

Coming into KCRW, When I checked the weather prior to departure there was a gust factor in the AS16 report. Checking again on descent the gust factor was gone so I didn't factor it into the vref approach speed. After the crash I checked it again and the gust factor was back. 

I'm guessing it was maybe unfortunate timing, but the plane literally dropped from the sky about 400' shy of the threshold.. happened really fast.

I'm wondering, why was there no wind shear warning? It literally just dropped, had time to throttle up but it was too late. Kinda scary considering how fast things happen.

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I had a stall warning and stick shaker in the 744.  I can honestly say that I have no idea why it happened.  Hasn't happened since and it was a first time since I've learned how to handle these planes.  So bizarre.

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When i saw the title i thougt it was for real, thank god it was you Nick (don't get me wrong, please). 

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6 hours ago, Orlaam said:

I had a stall warning and stick shaker in the 744. 

I had no stall / stick shaker warning - it just dropped from the sky. It was definitely a bumpy approach, but when it decided to drop, that was it it - just dropped.

It did make me think, thats why pilots make the big bucks. It was likely something I did wrong that caused it to drop, and if it wasn't then thats the risk a pilot takes everyday, it went from one of a hundred approaches to crash in 4 seconds.

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7 hours ago, Nick Dobda said:

I had no stall / stick shaker warning - it just dropped from the sky. It was definitely a bumpy approach, but when it decided to drop, that was it it - just dropped.

It did make me think, thats why pilots make the big bucks. It was likely something I did wrong that caused it to drop, and if it wasn't then thats the risk a pilot takes everyday, it went from one of a hundred approaches to crash in 4 seconds.

That is weird.  Sometimes it's just a software glitch too though.  Seems unlikely that you'd fall out of the sky just do to some gust changes.  I think when mine happened it was a result of the A/T being kicked off and potentially led to a loss of thrust for a brief moment.  IDK, I mean usually even when I turn off the A/T, I can move the thrust lever to match the engine and it doesn't affect much.  I may lose 2 or 3 knots but typically none.  It's not like the Dash 8 for example that will change speed dramatically for any reason. 

Hard to say without being able to go back and watch, which we can't unless we record it. 

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Thanks for feedback, sharing your experiences helps piece things together. I figure it could be a software glitch too - I was thinking along the lines of ASN updating the weather and the winds going from what it was before to what the new updated conditions were. The sim weather only updates over intervals, and I'm not sure exactly how the sim handles the updates.

On approach 6 knot headwind no gusts. ASN updates to a 4 knot tailwind, 8 knot gust. Potential 18 knot swing in wind right there hitting you instantaneously (assuming the update is instantaneous). Conditions were changing rapidly with storms rolling through at that particular time at that particular location last night. Still though, I would think that the stick shaker would have came on or something.

The only time I've had it drop like it did was in a stall... and those times the stick shaker was going and I was doing really bad things. 

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That is a complex topic.  I am doubtful the gust factor itself would drop you out of the sky.  Vref is stall speed + 30%.  That comes out to 30-35 knots for tyical Vref in the 737NG.  That would be a heck of a gust (30-35 knots above baseline wind).  Also, wind gusts typically add to wind speed (not subtract) and chance wind direction (can reduce your speed).  And finally, I would expect you stick shakers to go off if this was the case. 

Assuming this wasn't a software glitch, that sounds more like windsheer.  Depending what weather add-ons you have (ASN does it for sure), this is modeled.  The WXR in FSX/P3D is limited, but in the real aircraft the radars do scan for windshear.  This is a predictive windshear warning, so it doesn't mean for sure it exists, but could.  Windshear is a dangerous beast and most SOP I am aware of call for an immediate go-around for any predictive windshear warning.  You can drop rather rapidly in such a condition.  The PMDG has the windshear aural warning including, but I'm not sure how accurately the predictive scan actually works. 

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17 hours ago, Nick Dobda said:

I'm wondering, why was there no wind shear warning?

KCRW Yeager Airport is laid on top of three cut off hills.  The approaches are over valleys or a holler if you are from there (I when to High School there) and the winds can be tricky.  I have flown the PMDG B737 in there just a couple of time, but I have flown in real world many times in light twins and singles. In real world, that main runway is like a roller coaster... there's not much that is flat in WVa.

I've seen winds effects at places like Sedona AZ, which is on a plateau, do pretty strange things on short final.  You have to be very quick to correct, and always anticipating that something is going to hit the fan.

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Was there not a real life crash of a UPS affiliated cargo carrier last night at KCRW?

 

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It would be nice if you could view a log file from Active Sky to see any rendered windshear.

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5 hours ago, fppilot said:

Was there not a real life crash of a UPS affiliated cargo carrier last night at KCRW?

 

Air Cargo Carriers in a Short SD-330 possibly struck the wing tip on the runway and went tumbling down the hill into the trees.  It was OVC005 and FEW001 and performing a VOR-A approach.  I doubt the visibility was good, fog reported.  The two-man crew perished.

 

http://avherald.com/h?article=4a88f341

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Wow, that would be interesting if there was a real crash last night. I use as16 and as you mentioned wind shear is modeled... And i was anticipating a go around if the warning came up (for the first time ever!) like a real crash it was a chain of events. The weather I checked ahead of time had a headwind on Runway 5 so I had planned to arrive on it. Indy center was alive last night on vat sim, and I got cleared for visual 23. That threw me for a loop for a bit as I rechecked the weather and re calculated vref. Which is when I saw the gust was gone. Then I changed the fmc route. . By that time I saw I had missed top descent, so I had to adjust to catch the vertical and get below the clouds so I could do the visual approach. Finally got below clouds and started visual approach. Turned on the base but overshot. Clicked off the ap & at (while still flaps 10 & gear up) and wrestled it back to where it should be. Got everything out and just past minimums dropped out of the sky. 

 

Interesting you you mention the geography and the real world crazy winds caused by said geography. This is my second cross country flight marathon plan. It takes about ten months to complete. I'll plan to hit all major cities in every state. Plan to fly 200 - 300 miles per flight. This is the first all out crash I've had. I have had two close calls though, one of which was kcrw last time through here. Is the sim smart enough to incorporate the oddities associated with geography?

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And vref is 30% above stall you say... I was trying to maintain vref +5, I can remember it bouncing as low as 10 below what I was trying to maintain, I can't imagine it going 35 below what I was aiming for and going into a stall. Not to mention I didn't get a shaker.

would I get a shaker if it actually hit shear or would it do what it did, And simply drop?

if the latter is possible, then I guess the question for the programmer is can I get a shear condition in the sim with as16 in the ngx... And not get the wind shear! Warning?

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This is what happened... Less any warnings whatsoever. I've been wondering for the longest time when conditions would come together and I'd get a wind shear alert on an approach while having live atc.. Wondering how I would handle it. Would be a shame if a fluke prevented the warnings from going off. If I had a few seconds of warning I would have mashed the throttles and went around instead of riding it to the ground. 

Im not missing a setting or anything, right? You don't have to activate anything to get the warnings on do I? 

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So your AOA and speed were jumping all around like that?  I wouldn't even try that approach, even if I had no LLWS reported/warnings.  Plus that was simulating a microburst, which is different. 

The problem in the sim is that you lack RW warning systems and the ability to sense what is happening.  In the real world I believe you can kinda predict where you are in a situation and apply the appropriate escape maneuver.  The LLWS escape is to disconnect AP and AT and firewall the throttles, then aim for 15 degrees of pitch.  In microburst situations they will employ a variable pitch scenario, whereby you pitch down slightly then level off then climb out of it.  i

I just don't know that the sim is going to give you those real world chances to escape.  It's important to remember, no pilot is safe from adverse Wx.  If conditions are bad than anyone can be killed.

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Didn't realize this airport is enhanced by Orbx FTX US freeware pack.  I flew there from CMH in the Duke.  It seemed like the ILS was offset, and I don't see why.  It doesn't mention that on the plate.  Also, RW weather for now, but time set to day light gave me a low ceiling and fog.

2017-5-5_22-57-40-439.jpg

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3 hours ago, Nick Dobda said:

This is what happened... Less any warnings whatsoever. I've been wondering for the longest time when conditions would come together and I'd get a wind shear alert on an approach while having live atc.. Wondering how I would handle it. Would be a shame if a fluke prevented the warnings from going off. If I had a few seconds of warning I would have mashed the throttles and went around instead of riding it to the ground. 

Im not missing a setting or anything, right? You don't have to activate anything to get the warnings on do I? 

I would not entirely rely on the warning system. It's there to help you identifying dangerous situations, but not a substitute for your knowledge and experience. When you suddenly gain 40 knots of airspeed, you know it's possibly some serious windshear. I wouldn't wait to push that TOGA button when hundreds of lives depend on it.

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6 hours ago, Orlaam said:

It seemed like the ILS was offset

2017-5-5_22-57-40-439.jpg

Yes, when I turned to final it lined me up way left. I had to disconnect everything at that time and pull it back to line up properly. 

As the the last post discussed, I did a lot wrong, it was likely an unstable approach that should have been aborted anyway. I wasn't getting 30 knot gains, but it was jumping around maybe 10 knots. But I think it was an asn16 microburst that dropped me, just wondering why no warnings.

 

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Nick, I watched your video. That not only looks like windshear but also a major downdraft. I don't know what AS16 does or if this happens this way in real life. There are four anemometers on each quadrant in major airports and if there is a discrepancy of either 10 knots or more than 10 degrees in wind speed and direction the tower alerts aircraft. there were thunderstorms around, so I don't know what the NGX felt but your airspeed dropped to 70 KIAS so the 737 definitely stalled.

I believe something similar happened in real life to a Delta DC-10 was it ? at DFW many years ago. Did you make the decision to abort landing and added go around thrust when the wind shear alarm came on ?

 

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1 hour ago, ALF1 said:

I believe something similar happened in real life to a Delta DC-10 was it ?

WEL, you got the number of engines right, but it was the L-1011.

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Alberto, that's not my video. I picked this YouTube because the plane acted like this one did except I had no windshear warnings or stall warnings. In my case it just dropped.

it seems like I hit a microburst but had no advanced warning. I'm just now wondering if this scenerio can occur in the sim - that is to get a microburst with no advance warning.

I realize the sim isn't real life and there isn't really a windshear scanner scanning the virtual air, it is all programming. Just wondering if as16 told the ngx that a burst was coming and the ngx didn't receive the message to sound the warning or something.

 

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15 minutes ago, Nick Dobda said:

Alberto, that's not my video. I picked this YouTube because the plane acted like this one did except I had no windshear warnings or stall warnings. In my case it just dropped.

it seems like I hit a microburst but had no advanced warning. I'm just now wondering if this scenerio can occur in the sim - that is to get a microburst with no advance warning.

I realize the sim isn't real life and there isn't really a windshear scanner scanning the virtual air, it is all programming. Just wondering if as16 told the ngx that a burst was coming and the ngx didn't receive the message to sound the warning or something.

 

AS doesn't work that way.  It sends weather to the sim and the plane responds in real time.  No advance warning will be there.

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8 hours ago, Orlaam said:

AS doesn't work that way.  It sends weather to the sim and the plane responds in real time.  No advance warning will be there.

Ok, there is a windshear warning though, does as16 give the "windshear!" Audible warning? I know the Wx display should also display something too. In the video I found there is an audible warning, but I see there was nothing in the Wx display

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There are two windshear warning systems in the aircraft, not one. The first windshear warning that was developed is usually part of the EGPWS. This detects differences between inertial accelerations and pitot-static accelerations. A windshear will initially affect the pitot-static system, inertial velocities will take time to be affected. If the differences are large enough you get a windshear caution if the accelerations are forwards or updards and a windshear warning if they are downwards and backwards. It also senses OAT. If that starts dropping suddenly it's a sign of possible windshear in the vicinity and produces a windshear alert (steady amber, not flashing).

More recently, predictive windshear was developed which uses weather radar returns to detect high rain drop velocity, indicating a strong windshear. That shows a windshear graphic on the Wx and also gives an aural warning. The EGPWS windshear is now referred to as reactive windshear warning.

Whether PMDG simulate either I don't know. Data for predictive windshear should come from AS16/ASN. I've certainly seen windshear shown on the ASN map. Reactive windshear warning would be entirely a matter of PMDG modelling of reactive windshear. It's a shame that video doesn't show the weather radar otherwise it should also show whether the windshear warning is predictive or reactive.

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