Tom's Blog Two

[johnl]

Tom, when looking over the pilots shoulders back in the 50s, I seem to remember seeing a placard saying something like:
Don't operate engines continuously at xxxxRPMs
I don't remember the exact RPM, I think it was a vibration issue and it probably referred to cruise settings.

I've seen this, but can't remember where (RAF Dakota pilots notes?) or the exact revs. It was for a vibration issue and I think was somewhere in the 1700-1800 rpm range.

For the WR, I mostly cruised at "BOAC settings" of 30" MAP, 1900rpm or 29" MAP, 1800rpm - BOAC engineering were very suspicious of their stock of ex-RAF engines!

[Tom Goodrick]

I have found that the mistake I made was less a cause of the low airspeed than I had thought. The power gauge I used when discovering the low airspeed at low RPM was Pow_1200 which is a proper gauge reading the power directly. I had been confused because I discovered an old-style flow rate power gauge in Pow_DC4 while working with a DC-4. Next to that gauge in the Digital folder was Pow_DC3 which I had written many years ago and forgotten about but not used recently. At some time I had replaced it by the correct Pow_1200 gauge in the DC-3. (I now use a correct gauge in the DC-4.)

But when I fixed Pow_DC3 and ran a quick check of cruise speeds I did indeed see the smaller difference between speeds at the same power level. It is not clear why there was such a difference.

More work has to be done to see why using a lower RPM to generate the same power level (with boosted MAP) gives a lower airspeed in some cases.

I guess, John, you and many others just love flying the DC-3 so much you want to spend more time doing it so you prefer to fly slower. I do not. I prefer to fly at a reasonable speed closer to 150 KIAS as directed by several airlines who flew the DC-3 when it was young and healthy.

[Ed Burke]

I have searched unsuccessfully for something to back up my recollection that a widely accepted cruise power setting for the '3' in Australia was 30.5" 1850 rpm. John Lawler's figures seem to support that.

Ed

[Tom Goodrick]

I think we are getting to the crux of the problem: Some settings that should provide decent performance just do not give good performance in FS9.

I found the following:
Nominal___Actual________Power____KTS @5000 ft
30in 1900rpm 29.96__1907__48.15%___???
30.5in 1850rpm 30.55 1851__49.09%___<90.26 KTAS
29in 1800rpm__28.95__1801__45.51%__<93.4 KTAS

In each case, the aircraft could not hold the airspeed. The power seemed to be okay but the aircraft just continued to decelerate. This was in level flight on a standard day (Clear Skies) using the autopilot in HDG and ALT mode at 5000 ft.

[n7rg]

HI tom
found some more DC-3 stuff

www.douglasdc3.com/faa/a-669.pdf

[Tom Goodrick]

This info is interesting because 1) was written when the bird was young and 2) the CAA/FAA should be a neutral party, interested mainly in what can be done with the airplane rather than what should be done for the sake of longevity and economy.

[Allan_Lowson]

Two further sources of info:

A 1957 Quebecair DC-3 manual in easy to download chunks at :

pcmuseum.tripod.com/dc3/index.html

The dc3operatinglimitations.pdf file contains their cruise settings for a range of altitudes.

A larger download is the 1941/2 manual from the MAAM site (38MB)

www.maam.org/flightsim/enhance/r4d_enhance.htm#PILOTS OPERATING INSTRUCTIONS - C-47 AIRPLANE

There is a single page that shows all the operating settings - I'm about to head South to take my daughter back to London - but snow allowing should be back in a couple of days. I could print out the page and rescan it as a single page file then if it helps.

[Tom Goodrick]

Here is an email I received today from my brother-in-law, Arlow Skjegstadt who could really be "Ole" in the piece below:

Ole and Sven die in a snowmobiling accident, drunker than skunks and go to Hell. The Devil observes that they are really enjoying themselves. He says to them 'Doesn't the heat and smoke bother you?

Ole replies, 'Vell, ya know, ve're from nordern Minnesooota, DA land of snow an ice, an ve're yust happy fer a chance at varm up a little bit, ya know.'The devil decides that these two aren't miserable enough and turns up the heat even more.

When he returns to the room of the two guys from Minnesota, the devil finds them in light jackets and hats, grilling Walleye and drinking beer.

The devil is astonished and exclaims, 'Everyone down here is in abject misery,and you two seem to be enjoying yourselves?' Sven replies, 'Vell, ya know, ve don't git too much varm veather up dere at DA Falls, so ve've yust got at haff a fish fry vhen DA veather's dis nice.'

The devil is absolutely furious. He can hardly see straight. Finally he comes up with the answer.The two guys love the heat because they have been cold all their lives. The devil decides to turn all the heat off in Hell. The next morning, the temperature is 60 below zero, icicles are hanging everywhere, and people are shivering so bad that they are unable to wail, moan or gnash their teeth.

The devil smiles and heads for the room with Ole and Sven. He gets there and finds them back in their parkas, bomber hats, and mittens. They are jumping up and down, cheering, yelling and screaming like mad men. The devil is dumbfounded, 'I don't understand, when I turn up the heat you're happy. Now its freezing cold and you're still happy. What's wrong with you two?

They both look at the devil in surprise and say, 'Vell, don't ya know, if hell iss froze over, dat must mean DA Vikings von DA Super Bowl'


www.sea-zyme.com

Arlow and his wife Carol spend their winters in Orlando and summers in Minneapolis. They see us in spring and fall as they travel between the two places.

GO VIKS!

[Tom Goodrick]

It's time for an update on my Wii activities and, yes, the four black kittens - now cats - with their Momma are still with us. We have 8 cats in total, living in two separate sections of our house except for separate runs around the house.

These days I get most of my exercise from Wii Sports RESORT which has 12 activities. Its Table Tennis has replaced the Tennis on the original Sorts disk as my main wake-up activity combined with 100-pin bowling. There is now an 18 hole golf course for both "regular golf" and Frisbee Golf. The scenario is on an island where it is perpetual summer time and where there are always fun activities using the surrounding water and using various luxery spas on the island.

Back in my early college days I lived in a dorm also frequented by guys on sports scholarships. That mean't we had very lively ping pong competitions. I learned some serious ping ponging. The Table Tennis in this game matches anythiing I played in college. You can play fast and close or strategic and back 6 feet from the edge of the table. All types of "English" are effective.

The controller that comes with this game is an extension to your normal Wii controller that gives additional accelerometers. A difference this produces, between the old Tennis and this Table Tennis, is that this controller tracks your wrist rotations in addition to your arm movement. I have had trouble remembering to flip my wrist between fore hand and back hand swings. In the old Tennis the wrist was essentially fixed with the arm. There was English based on arm movements. Combine that now with English based on wrist and arm movements and you have neat ball action that is very realistic. It is also tiring and conducive to all sorts of aches and pains. You end up jumping around a bit. On the old Tennis I locked in at about 2150 with a 50 point variation. So far I am moving consitently between 500 and 1000 on Table Tennis. If you are a hot ping ponger, you'll make toast of the players rated under 400 and take most of the battles leading up to the 500-point rating. You gain or lose several points in ratings for every point difference in a game. You are assigned the opponent with a rating closest above yours. I have a few complaints about the referrees and about some game mechanics.

The game is played in an area set aside next to the swimming pool of your hotel. One neat aspect is when you get a slam shot (hit as hard as you can), if it does not pop your opponent on the forehead, your shot ends up in the pool.

But for us Flight Simmers, there is a flight sim where you fly a biplane off the surface of the sea and buzz the islands in the resort area looking for targets that name land marks and for balloons. You can also fly dogfights but I have not done that yet. I prefer the unstructured flying where you pop an occasional balloon while doing wild aerobatics.

To control flight you point the controller's end toward the screen, roll it left and right to bank, tilt up to pitch up and down to pitch down. It does both slow rolls and snap rolls. I leave the throttle alone as it seems to be set about right. But you can speed up the engine by moving the controller forward (toward the screen.

When you do screw up, you pilot Mii ejects and rides a chute down, then the flight resumes some distance away. You "score" by poping balloons that are tied to just about anything that moves and also poping icons that appear in various spots over points of interest.

100 pin bowling is neat. There is also regular 10-pin bowling but with 100 pins you can have more fun. Rolling your wrist as you release the ball gives a good spin that mixes up the 100 pins enough so you can get a few strikes now and then. My high score is 2260 but the average is about 1700. You can notice the effect of the controller by comparing this 10-pin bowling with that in the original Sports disck. Picking up spares in the 10-pin bowling is interesting. These splits are spliiiiiiits!

Good fun and exercise that gets you off your butt from flying.

[flaminghotsauce]

COOL! I knew nothing about this Wii game. I just bought it on Amazon. It's on it's way. Thanks Tom.

[Tom Goodrick]

Good. Your whole family will find something they like there. The choices are sword fighting (they call it "play"), basketball, power boating on jet skis, wakw boarding behind boats, table tennis, frisbee for targets and for golf, regular golf, archery, bowling as mentioned, flying including skydiving, sight-seeing and dogfighting.

The aircraft is a monoplane with pontoons and an open cockpit.

All games can be played agianst computer opponents or human opponents. To retain houshold equanimity, I recommend playing it against computer oppopnents!

[flaminghotsauce]

Well, I did buy a second plugin device for the other Wii-mote so we can do two players.... I'm REALLY looking forward to having backspin on a golf ball. The Table Tennis looks really good too. This is going to be a blast.

[n7rg]

Hay Tom
Are those the kind of numbers you were looking for 20, 20, 105 knots. and it will hold that speed.

[Tom Goodrick]

They sure aren't the numbers I was looking for. The power is way too low. Why go so slow? 50% power is where I like to cruise the DC-3. I'd rather cruise at a decent speed (closer to 150 knots) arrive early over the destination and then find ways to loiter until making a final approach right on the target time. Trick is to stay close and not wait too long.

[n7rg]

hi
your right. But point I trying to make is, that you said.

I found the following:
Nominal___Actual________Power____KTS @5000 ft
30in 1900rpm 29.96__1907__48.15%___???
30.5in 1850rpm 30.55 1851__49.09%___<90.26 KTAS
29in 1800rpm__28.95__1801__45.51%__<93.4 KTAS

In each case, the aircraft could not hold the airspeed. The power seemed to be okay but the aircraft just continued to decelerate. This was in level flight on a standard day (Clear Skies) using the autopilot in HDG and ALT mode at 5000 ft.

And I was trying to show you, that if you set Flight Dynamics up right, you could get it to hold the airspeed at 25.33% power.
to get 150 Knots I moved MP to 31in @ 2000 rpm power 45.67. Now to start fine tuning the FD with your new gauges.



Rich