R99, does the Engineers panel show two lights for the stairs? one for the pressurized door, and the other for the stairs? that's one function my cockpit doesn't show....I'll look in my Continental flight manual and see if they list it?

I'm posting a comment made by Hominid back in 2011. it's about the weather, and the flight path. It's good information that I need in my testing......Hominid hasn't logged in for a long time? I'm a little concerned about him. I'll email him and see if he is ok. his last login was January 12, 2015




There have been some claims that the weather was very bad as Flight 305 came through the Vancouver-Portland area. Some of this has been in relation to someone in a helicopter at unspecified locations and times, but at 2500'. Some has been about the Columbia River Gorge (which extends many miles to the east along the river starting a few miles east of Portland and Vancouver, and is basically the border between Oregon and Washington in that area).

The claims are inconsistent with NWS data that has been reproduced at WeatherUnderground.com, but the weather data FBI agent Carr posted (then, Georger reposted) provides an opportunity to check about the claims using data that was actually produced by the predecesor to the National Weather Service on that night. The data includes reports of weather conditions for Portland International Airport (PDX), Troutdale airport, Toledo airport and The Dalles at 8pm (image 6b), 9pm (image 5b) and 9:17pm (part 1 of image 1b) PST. Troutdale is a little east of PDX practically at the mouth of the gorge. The Dalles is further east, actually in the gorge. Toledo is a few minutes north of the Vancouver plain.

PORTLAND AIRPORT

The maximum cloud coverage ("overcast") was at a base of 5000' for all three observations, from 8pm through 9:17pm. Over that time frame, the "broken" layer base rose from 2700' to 3100' to 3500' (all AGL). In other words, the layer that (with any lower layer) provided over .5 coverage was rising over the period. The sky was clearing below 3500' and a helo at 2500' AGL would have been below most of the cloud coverage the entire time.

Over that same time sequence, an 8pm "scattered" layer at 1500' AGL was gone at 9pm, but was then back at 9:17. In place of that scattered layer, a few "CUFRA" at 1500' were reported at the intermediate time (when the scattered layer had disappeared). I believe from this that the CUFRA was the remains of the scattered layer of clouds rather than clouds that were ripped away from larger clouds by winds, or formed by the higher clouds. That is, the scattered clouds had shrunk to almost nothing and were identified as CUFRA because of their appearance. A 2500' helo would be above this base in clear air or scattered clouds.

Also, the horizontal visibility (air "clear-ness") peaked at the intermediate observation time. It was 7 statute miles (SM) at 8pm, went up to 10SM at 9pm (when the low clouds were disappearing), then went back to 6SM at 9:17. Light showers were reported at each time.

The existence of the data for 8pm and 9pm in the data Carr posted gives us an opportunity to fill in between the 7pm and 10pm data from WeatherUnderground. Combining data from the sources shows that the wind speed went from 4.6mph at 7pm, to 11.5mph at 8pm, to 12.67mph at 9pm, to 11.5mph at 10pm. The wind speed went abruptly up from nearly dead calm between 7pm and 8pm, then stayed approximately constant for the next two hours.

 

Similarly, the wind direction changed from 130° (SE) at 7pm (when there was barely any wind) to 270° (W) at 8pm to 190° (S) at 9pm and to 200° (SSW) at 10pm. The abrupt change of the wind to west at 8pm, then back to SSW at 9pm is intriguing. (BTW: wind directions are plus or minus 5°.)

Note how some possibly significant transient weather data is missed by WeatherUnderground because of their giving data for only every third hour.

The wind direction for 7pm is basically meaningless because of the fact that the wind speed was so low. Winds often change direction frequently and erratically when their speeds are low. This is partly because the small perterbations in various directions are what remain when the sustained wind drops to near zero. The low wind has no "conviction." It's "indecisive."

Other than the 8pm west wind, I do not see change much different than the changes for earlier and later days. If you're looking at the WeatherUnderground page for PDX on 11/24/71, you can select to view data for the entire week at the top of the data table.)(Also see attached.)

However, the virtual dead calm from 4pm to 7pm is not present for days shortly before or after the 24th. What does that calm, followed by the abruptly higher speed and short-term west wind, imply for weather near Portland in the following hour? It looks like the 3 hours of calm was a calm before a weak windstorm, not a "calm before THE storm." But it may have just been a random situation of two 3-hourly observations in a row being the same.

TROUTDALE AIRPORT

From 8pm to 9pm to 9:17pm the base of the sky obscuring (overcast) cloud layer rose from 4000' to 6000' AGL. At 8pm no lower layer was reported. At 9pm a layer of "broken" clouds (over .5 coverage) developed at a little under 2200' AGL. It rose to 4000' AGL at 9:17, at which time a "scattered" layer had developed at 1500', the horizontal visibility had dropped to 7SM (from 10), and the wind direction had changed from 220° (SSW) to 270° (W). (wind directions ±5°) Over the period, wind speed had gone from 7kt to 21kt/24mph (9pm) to 12kt. Light showers at 8pm, very light at 9pm, and back to light at 9:17pm.

In general, showers and vertical visibility diminished and wind increased for the intermediate observation. Then the wind direction changed and the horizontal visibility dropped a bit. The cloud cover heights increased, but a lower coverage layer appeared. A 2500' helo could have been above a cloud base at any time after 8pm.

Generally mild weather at the mouth of the gorge, but the wind did pick up a bit after 8pm.

THE DALLES

Much of the info for 8pm (just below the line for Yakima "YKM") is illegible in the 8pm report. It appears that the wind was 9kt from 200°.

At 9pm there was a "scattered" cloud layer at 1500' and a "broken" layer at an estimated 6000' (AGL). Visibility was 15SM. 6kt wind from 310°. No precipitation was reported for 9pm, rain having begun at 8:04 and ended at 8:06 (2 minutes of rain).

At 9:17pm the scattered layer had risen to 2500' and the broken layer had fallen to 4000'. Light showers, wind 15kt (17mph) from 270° (W). The 9:17 report included "chance of light XC" (whatever that meant).

For the entire day, the WeatherUnderground site indicates that The Dalles got only .08" of rain.

In general, wind dropped and changed direction a bit at 9pm then went back some at 9:17. Cloud layer heights changed.

Mild weather at this point in the gorge, except that the wind did go up a bit at 9:17.

TOLEDO

Toledo was not on the 9:17 report in image 1b, as far as I could tell. At 8pm its report said 3000' AGL overcast (complete cover), 12SM visibility, very light showers, 5kt from 190°, and rain had begun at 7:35. At 9pm the report was 3000' scattered, 3400' measured ceiling/overcast, the same visibility, no rain, 6kt (virtually the same) from the same 190°, and rain had ended at 8:05.

Very mild conditions at both 8pm and 9pm a few miles north of Vancouver. A 2500' helo would have been under the cloud base.

I just spent a half hour setting up the sim to record the first leg, got up in the air  and was flying for almost 20 minutes when a power surge hit shutting my computer down whats even more funny is I have a backup battery I got a couple weeks ago, but didn't hook it up yet.

I just ran the first flight test from start to finish (seattle to Portland)

Temp....43 degrees (ground)
Tat temp at 10,000 -8 transcripts read -7
Average speed 170
average ground speed 194
headwind most of the way 22 knots 180 degrees

I crossed the Columbia with a time of 41:15 minutes. I believe they crossed the river at 40 minutes. I have the flight recorded for replay, so I can find out where I was at any given time, and find out any error's (if any) can be found. I'm pretty sure I has 34:23 crossing the Lewis river. I think the map shows 33?

+++ 

well, I have to verify the timing, and then do several more runs of the same test to insure accuracy. the time difference was just past Toledo. I arrived at almost the same time as the map, but it skews from Toledo down to the crossing of the Columbia. if it's correct (not verified yet) then the timing is off.

I had everything set correctly, and maintained altitudes, and speeds, temps etc. I'm going to go over the data this evening...

R99, I'm having issues with ground speed, I get lower speeds with the winds everyone is factoring in. the issue starts after turning at Toledo. the ground speed drops to about 185 with winds at 27 @225 degree's. my KIAS also goes up to 180?

what could be my issue, I have everything set correctly, temps, speeds, fuel flow matches, but to correct I have to back off on the throttle, or hit the speed brakes? I'm running with the plane nearly empty cargo wise, and put some weight in for luggage. I'll have to check the exact weight prior to takeoff....

Are you duplicating flap settings at the same times as in the Transcript?

R99, I'm having issues with ground speed, I get lower speeds with the winds everyone is factoring in. the issue starts after turning at Toledo. the ground speed drops to about 185 with winds at 27 @225 degree's. my KIAS also goes up to 180?

what could be my issue, I have everything set correctly, temps, speeds, fuel flow matches, but to correct I have to back off on the throttle, or hit the speed brakes? I'm running with the plane nearly empty cargo wise, and put some weight in for luggage. I'll have to check the exact weight prior to takeoff....

Okay!

The KIAS is read directly from the Airspeed Indicator.  It is assumed that there is no pressure error in the airspeed system and no mechanical error in the Airspeed Indicator instrument (for airliners, these are excellent assumptions).  The Airspeed Indicator should be showing 170 Knots Indicated Air Speed (KIAS), or very close to it since it was their target air speed at that point in the flight.

The TAS is the True Air Speed of the airliner with respect to the air mass through which it is flying.  TAS has to be calculated.  The Air Speed indicator is calibrated to read values for a "standard atmosphere" and those values must be corrected for non-standard values of atmospheric pressure and temperature.  The ATC controllers passed the actual sea level atmospheric pressure (in the area they were flying at that specific time) to the NWA 305 crew frequently and the crew could determine the temperature outside the aircraft from instruments inside the cockpit.  The TAS was about 194 Knots True Air Speed (KTAS).

The KIAS and KTAS have absolutely nothing to do with the wind velocity or its direction.

The ESTIMATED wind velocity of 27 Knots from 225 degrees True (with respect to the grid lines) is a good estimate of what NWA was actually experiencing in the Portland area.

ASSUMING that NWA was tracking down the centerline of V-23 from the Mayfield (now Malay) Intersection to the Portland (now Battleground) VORTAC, it would maintain a course (or track) of 170 degrees True (with respect to the grid lines).

Plugging the appropriate values from above into a pilot's hand computer, NWA 305 would have a 22 Knot crosswind component from the right and an 18 knot headwind component.  To stay on the exact centerline of V-23, the airliner would have to "crab" slightly to the right.  The 18 Knot headwind component is subtracted directly from the 194 Knot TAS to give a Ground Speed of 176 Knots.

In turning to the Southeast at the Mayfield (Malay) Intersection, the Ground Speed should increase slightly but there would be no changes whatsoever in the KIAS or KTAS.  So the cause of your problem is not evident from your information.

Check that you have the wind values set correctly using the True Course system.  Otherwise, there is no logical explanation as to why your KIAS is increasing by simply turning to the Southeast.

Shutter, for unknown reasons, I cannot view this video using either IE-11 or Chrome.  But the winds at 10,000 feet are the only ones that matter here.