Karoliina’s pineapple smoothie (recipe)

You need the followings:
- 1 liter: Tropicana Pineapple juice.
- 1 package of coconut milk
- 3 bananas

Mix together until the mix is smooth (with power mixer).

Hypotenuse and catheti and how blending makes wetted area not larger but actually smaller!

Most aircraft have larger than necessary wetted area and not so optimal body shape. One could think without thinking in more detail that wetted area is saved by lofting the plane so that the engine cowling is part of the main fairing and then there is a minimum canopy added on top of that.

However, a little thinking further: which one is the shortest route always, hypotenuse or catheti? Unlike the first thing which comes to mind when looking at planes and saving wetted area, instead of having this complicated shape, actually having more volume and fairing everything in the single form actually produces not only easiest path to the airflow, but also it produces lowest possible wetted area. So making the fuselage larger by removing canopy and putting the cockpit inside the main shape decreases wetted area and drag instead of increasing it. The shallower angle for windows does not decrease the visibility – the visibility can remain still the same. The only problem comes from the optical quality of the windows – as you are looking them from angled direction, you are looking through more plexiglass than you otherwise would and it can degrade the visibility. However – the visibility directly forwards is usually not so good in single engine aircraft which have engine in the front and it is neither better on planes without engine on front since somehow designers seem to not think that people would like to see straight forward very well too. Some twin engine planes have very high panels and poor visibility forwards despite of the fact not having the engine in front would make it possible to make the forward visibility a lot better than that.

So the design on CAD system becomes easy when the shape is not complicated but super simple. And in turn the super simple shape (convex to all directions though, in that sense not so simple, but I mean it is a single loft) has the best drag coefficient and the best wetted area too. At times it feels unbelievable that the solution can be so simple (and I have difficulty to believe it myself when looking e.g. our shared ownership Diamond DA40, it has many shapes, parts and forms), but who says that it has to have so many shapes. Nobody. So it will not have so many different shapes and forms if one shape can do it all. And who says the instrument panel needs to be panel and everything laid out to the panel? Nobody again. A bit more creativity and a lot better forward visibility is achieved despite of not having a bubble canopy and despite of having a pressurized fuselage.

Blending the fuselage to the wings increases frontal area. But who cares about the frontal area. It has very little effect to the drag in airplanes. It is all about wetted area and saving in the wetted area (in addition to maximizing the laminar flow). So blending the wing decreases wetted area – hypotenuse again, it is not a good idea to follow catheti. And the air likes that too – in fuselage wing joint the airflow can not sustain laminar flow. But what if you eliminate the joint and at the same time save in the wetted area. Great stuff.

One could say that it is hard to make a door to a such fuselage. Yes it is hard to make a door. But the solution for the door is to eliminate the door. A hatch that has no hinges and that is larger than the hole is the most light weight door one can imagine. It does not require complicated mechanism to hold it on place and it does not require lots of latches. It holds on place by itself because of the air pressure differential. It can be locked with a lot lesser heavy duty mechanics from inside to the fuselage. And how to ensure the hatch does not ever get out of the hole? That is super easy too: the hole and hatch can be circular and there is no way to put a larger circle out of a smaller circular hole. Not even magicians can do that!

Now then the window problem:
- to glue windows on pressurized fuselage, how to make sure the windows don’t rip themselves out – how to glue them on place. Keep it simple and stupid solution: glue them to the inside so that they are larger than the hole in the fuselage. Now what, we have a problem that there is a dent outside of the fuselage on the window area which is really bad for the airflow. No problem again, there can be a simple non-pressurized window that is glued to the outside and faired level with the fuselage around it. It is also a fail-safe: if the windows that are exposed to outside get scratches, no problem, it does not affect the pressurized fuselage – these windows can be replaced fairly easily. And guess what, no bolts are needed, no rivets are needed, very simple.

Then how to get the blended fuselage to work with pressurization. Again super simple: the blend can be fairing on the outside and the pressure vessel can be tubular with completely circular cross section inside.

We arrived safely to home Wednesday 19.7.2009 evening. The trip was finally over and i felt so good to be at home with my cats. There is lot of stories to tell, many blog articles are waiting to be published. i just need to finish them and chose pictures attached. We got around 200Gigabytes of picture and video material with our EOS 5D mk II .

Our route was following N756DS route in Great Circle mapper

That makes about 9000 Nautical miles and that is not counting yet my Instrument training in Palo Alto or that many legs were not great circle but airways via fixes. You can find more precise tracks and IFR plans from Flightaware N756DS

Palo Alto, completing the IR training

I started my IR training in West Valley Flying Club ( www.wvfc.org ) in San Francisco area . The plan was to get fast and cheap instrument rating. Soon I noticed that if you really like to get easy IR as as quickly and fast, the San Francisco bay area is worst possible choice. If you like to get good IR with it you can fly about any busy airspace, it is excellent choice.

First surprises were that American airspace system and regulations differ a lot from European ones and San Francisco bay area airspace structure is really complicated and busy. Helsinki area is about small village compared to SF-bay area. There, Palo Alto, just one of dozens local general aviation airports has as much GA-airplanes that exists in all Finland. It was also surprise that radio fraseology differs a lot from European one and if you are non native English speaker, busy fast IFR radio communications needs some time to adapt.

It is also not the fastest and cheapest to start IR training with Cirrus SR20 with Avidyne glass cockpit. When I started the training, Cirrus was our number one alternative and WVFC did not had Diamond in this time. They charge $199 or $214 for SR20, $164 for C172/G1000 but Steam Gauge Cessna or Piper you may get around $100 . Cirrus is also not considered as ordinary airplane for WVFC, it needs minimum 11 hours type training and special check ride called phase check.

Flying club as like WVFC was not a fastest way to get training, there is also other members booking planes and flight instructors and therefore you can’t fly when you want to do so. Some flight schools may designate plane and instructor for you all of the course. This Flying club system is just not most cost efficient if you are not local but coming from distant country and need to pay hotel and car rental for every day you are flying or not. Also Silicon valley is not the cheapest place to stay.

When i started my flight training 2008 I Strongly underestimated my schedule, I scheduled one month period for flight training. It was strongly underestimated, i just could not got booked enough plane and instructor to get training completed. I spent many days just for keeping vacation, that was not bad idea at all in SF bay area. IR Training is also and work, so it is not bad idea to have some free time between sessions. I had plan to return autumn to complete training but this did not happen. In 2008 trip I also learned that many things can go wrong in paperwork. I had plan to get FAA Medical and FAA PPL . When i was already in Palo Alto, FAA told to me that they did’t approve my translated medical records because they are not translated by FAA approved translator. Even today, i don’t know what is and where to find FAA approved Finnish to English translator. For next trip, I asked doctors to write their statements in English and sign them as originals to avoid this translation problem.

I returned spring 2009 continuing my instrument training, I chose cheaper C172 G1000 plane that the club had more of them than Cirrus SR20’s and i got in practice designated flight instructor. I think that also economical depression affected so that instructors and planes were no longer so booked than spring 2008 . Now I also has basically all paperwork done. I had European JAA and FAA medical and i had file application for FAA Restricted PPL .

When I returned after one year since i had my previous instrument training, it needed several hours training just to get level where I was year ago when i left. In Spring 2009 i did written test and got basically training program done but once again bad luck with paper work. I got my FAA Restricted PPL based on European pilot’s license but i was unable to get appointment booked to San Jose FSDO and therefore I was unable to have Check ride.

Now in this trip, i finally had everything done. I had training done, I had all medicals in my hand, i had appointment booked to San Jose FSDO and I had check ride booked. The trip from Florida to Palo alto took couple of days longer than estimated and we needed to re-schedule my check ride to Monday 27 July. Now i had couple of days time to refresh my IR skills before check ride. Then Monday i was thinking that everything is ready and we started ground part of checkride but it was interrupted n beginning because there was couple on flight instructor signatures missing from my logbook. The Check ride was then re-scheduled Wednesday 29.

In Wednesday, we finally were able to begin my checkride. I had Tom Hornak as my check ride pilot. At first he went thru my application and logbook, then checked airplane documents, maintenance records etc. Then he did tho oral part, series of good questions like what i would do in complete radio failure situation, some details from approach plates, how to get weather briefing etc. Then started actual check ride, I filed flight plan to Stockton ( KSCK, route SJC V334 SUNOL V195 ECA ). In Stockton we did VOR rwy 21, touch an go, then continued GPA A to Tracy ( KTCY ) and that approach we did as partial panel. From tracy missed approach we did couple of holds and then ILS rwy 25R to Livermore. That was the check ride and I was really happy and relieved when Tom said that I passed. Finally long lasting dream and couple of years long project was completed.

About actual training, my instructors in West Valley, Scott Stauter and Brian Elliot give excellent instruction. Wvfc had excellent facilities, wide variety of planes to chose, starting from old steam gauge Cessnas to modern glass cockpit Diamond Star DA40, TwinStar DA42 Cirrus SR20 and SR22 and several G1000 Cessna 172 . They also have Frasca G1000 simulator that we used as mush as we could for my training. There is several good reasons to use simulator. With simulator you can practice mush more approaches in same time, you can practice more fault conditions than in real plane and it costs 100 dollars less for hour than aircraft.

Then there is question, should you get your instrument training with glass or with steam gauges. As my personal opinion, if you plan to fly modern glass cockpit planes, you should get your training with glass. Flying glass needs so much different skills. Reading the attitude indicator , altitude and airspeed is the easy thing. Much more skills is needed to program flight plan, selecting approaches etc. Your most busy times comes when you approach your target airport, get weather and you are cleared to approach. In this situation you need to program right approach into system, brief it to yourself and be all of the time up to date with radio traffic and on course fly the plane. You can practice most of the things in ground but then real thing is to do it in busy conditions in flying airplane. Partial panel is also completely different with glass and steam. In practice difference between Cirrus with Avidyne/GNS430 or Diamond with G1000 is not as big at all. Garmin logic to program flight plans and approaches is very similar in both of these.

Other question is that should you get your IFR training done in some peaceful little city or in busy San Francisco bay airspace.If you like to get it done cheaply and fast, small city flight school may be good choice. If you like to get your skills to level where about no airspace is too busy to you take SF-Bay but remember
that you may not got it done with minimum hours.

Now, i have crossed north American continent twice and passed many big cities Class-B air spaces but i have not yet found as busy as SF-bay area . Some rumors tell that Los Angeles area is even worse but i have not yet had change to try.

Lessons learned. Best is not cheapest and fastest. If you fly glass, take your IR with glass even it costs more. If you plan to fly in busy airspaces get your IR there but you need more hours. If you need split your training to multiple chunks, it causes some penalty, may be 10 hours to get level you where uou were when you left. If you are flying IR in flying club, verify that you have plane and instructor available or you can’t keep your schedule. Be prepared that what ever you try, some factors may ruin your schedule. Prepare your paperwork lot of advance, book appointments to FSDO etc lot of advance. Remember, that if there is something wrong in papers, it may took two months round trip to fix it.

And at last but not least, IFR if fun, i don’t regret that i started . I think that getting training in SF-bay and with glass was right choice but it definately was not fastest or cheapest one.

Pueblo to Palo Alto , Over the rockies and thru the burning hell

We started Tuesday 21st waking up early morning and got ourself to airport around 8am morning.It is best time to cross mountains in morning when air is not yet hot and most of cumulonimbuses appear in afternoon. It was once again Karoliina’s turn to fly, we decided to go as VFR via pass thru mountains. In IFR minimum enroute altitude
should be highest point enroute rounded upper thousand feet plus 2000 feet. In VFR is enough not touching terrain. We were uncertain how well Diamond would climb in worm air with three full size adults inside and we decided not to take any rists. We still needed to climb to 12500 ft but Diamond did it without any problems.

First leg and mountain crossing went without any problems in excellent weather. Our first stop was in Farmington, New Mexico (KFMN), elevation 5500ft. This airport had nice FBO with air-conditioned restrooms facilities for flight planning we took tanks full of fuel and planned to go Grand Canyon, KGCN .

The route to Gran canyon was really great scenic route, sceneries familiar to most of us from western movies . First we flew over monument Valley and then over grand canyon. When we arrived Gran Canyon, there was thunderstorm just over airport and we decided to go on.

We landed Kingman, KIGM, elevation 3360ft . That place was like burning hell, temperature around 40 degrees of celsius. We got there in place where was no cover from sun, airport staff advised us that restrooms are in passenger terminal and there was no other
way back to apron expect left someone open to gate and we did not find any flight planning facilities. The place was also graveyard of DHL american fleet.

From Kingman we continued to Lancaster, KWJF, hot but not so hot than Kingman and there was even some wind to make it to feel more comfortable. There was also good facilities air conditioned building to do flight planning. We decided to file IFR plan to Palo Alto via route PMD V197 EHF AVE V137 ROM V485 LICKE and it was Kate’s turn to fly IFR . When we took off, it was evening twilight and soon it was completely dark night but weather was good. I must say that I don’t feel comfortable to fly in night in mountaineus terrain. If engine quits, there is no way to chose good
place for forced landing. In plains, there is good possibility that terrain under is not so bad.

We landed Palo alto 22.56, we had some probems to get taxi and finally got to our motel Standford Motor inn around 1am.I must say that i felt really exhausted, long and hot flight day.

If ypu would like see more pictures, please look our N756DS Picasa callery

St Louis to Pueblo, CO , Beauty and Beast

We kept Sunday just for resting with our friends, in Chrissi’s and Randi’s place. On Monday morning we checked weather and noticed that there is front with thunder storms moving across our route. We filed IFR plan to Salina (KSLN) via route 1H0 SNYDR V12 OJC V508 TOP V4 ZITIK KSLN but then we saw thunderstorms front of us and decided to land in Topeka (KTOP) to wait front pas us. We waited couple of hours in Topeka FBO weather briefing room and followed from Nexrad thunderstorms moving south east. After thunderstorms passed, we filed IFR plan to Hays (KHYS) via route
V4 SLN V508 KHYS. At beginning of route we needed to fly in rain but still in VMC.

We landed to Hays in perfect VMC conditions and sunny weather but there was big cumulonimbus growing nearby and it looked threatening. We decided togo on as
quickly as possible and now it was Karoliina’s turn to fly. We filed route to Pueblo via V244 but
soon we needed to ask defer from our course because there was really beauty monster, huge thundercloud from our right side. I have never seen same time s beauty but also so threatening thundercloud before. It did not cause a actual danger to us because is was easy to see and avoid. I just looked lightnings sriking from cloud to ground. There was other thunderstorm to go around that just passed Pueblo. We were able to land Pueblo without any problems.

In Pueblo, there was local FBO, Flower Aviation, they booked Hotel to us and arranged transport. We spend night in La Quinta inn after long and challenging flight day.

Second Day From Florida to St Louis

We had plan to leave Florida as early as possible to avoid bad weather but we were so tired because we did had so much lack of sleep during last few days.
We woke up in Jacksonville Ramada Inn 9 am and arrived with car to Sterling Flight in Craig Municipal airport ( KCRG ) 11 am. There was front of
bad weather arriving from north west. Kate needed to return our rental car to Jacksonville International Airport ( KJAX ) and Karoliina flew N756DS
there. Cloud ceiling was already low and there was moderate precipitation. Kate got rental car return point but there person in Rental car return did not know
how to get General Aviation terminal ( FBO ), she was completely unaware that such thing as general aviation even exists and could only say
that you need to go airliner terminal. Kate finally found FBO by walking and sweating half an hour in the hot Florida weather.

Karoliina arrived the same time
Sheltair FBO. We checked weather and noticed that we need to leave quickly to avoid getting worse weather. After take off from KJAX we were able to climb
to 2000ft . Soo Ceiling started to go lower and we ended to fly below clouds under 1000ft in uncontrolled Airspace over Florida swamps but still
safely within VFR minimums. After half of hour ceiling started to raise and we were in perfect weather for rest of this leg. We arrived safely to our
refueling stop Russel Rome airport ( KRMG ) near by Atlanta.

From KRMG our next leg was to St Louis, Missouri. Ceiling was high and we were able to cruise 4000ft . We used VFR Flight following for both legs
to get warnings about possible severe weather or traffic. That was a easy leg, just put flight plan to G1000 and autopilot on. Our target for
this leg was Creve Couer airport ( 1H0 ) . We arrived there about 9pm just around sunset. The airport is under complex St Louis Class B airspace.
The G1000 was very useful showing all airspace borders and altitude limits. VFR Flight following was also useful when arriving to unfamiliar
complex airspace.

Weather front is just arriving to St Louis

When we landed, Karoliina called our friends Chrissi and Randi, the Cozy Girrrls. They arrived soon with their minivan that had already back seat removed
for carrying things to Oshkosh. We get in to their van and let our Bird to rest for night. Chrissi and Randi are experimental aircraft builders and they
run their own small experimental aircraft parts business CG Products. They do really great work and perfect professional quality parts in
their workshop.

Good night to N756DS for good flight

The Pretty bird got a new home – day 1

Our first day, we drove from Miami to Jacksonville, 6 hours via Inter State 95.
Karoliina was using N97 to write mails to our insurance broker. We got all needed work for insurance done just 15 minutes before we arrived to pick up plane from Sterling Flight training.

There the our new Pretty Bird was waiting for us. Just fresh annual done and no
extra repairs needed. We decided to go for test flight with Sterling flight instructor and at the same time get checked out to the plane. First Touch and Go’s in At Augustine ( KSGX ) and then scenery route to Space Coast Regional Airport ( KTIX ).

It would be big sin to go so near of Nasa Cape Caneveral launch site and not even seeing it. Sad that so distant but we have wery tight schedule. Next morning we needed
to fly the plane to St Louis.

In KTIX we switched pilots and it was Karoliina’s turn to fly. She went to St Augustine to do touch and go’s as night flight. We happily landed back to KCRG 10.00 pm. Then it was time to get some sleep in hotel, happy but really very tired.

MIK kerhoilta 11.3. C210 siirtolento USA->Suomi. Klo 17.00 SIL luokka, vapaa pääsy

Malmin ilmailukerhon luentosarja jatkuu: C210 siirtolento USA->Suomi SIL-luokassa.
Luennoitsijat: Ilari Härkönen ja Matti Suuronen, jotka itse lensivät ko. koneen Grönlannin yli Eurooppaan.

Paikka SIL-luokka, Malmin lentoasema. Klo 17.00-
Tilaisuuteen on vapaa pääsy. Tervetuloa.

OT: MIK lectures event Today evening 18-21 at Helsinki-Malmi airport/SIL class room

Off-topic: This is just for those who read this blog but are not reading my other blogs and are located in Helsinki area Finland. We have a flying club evening event Today at Malmi airport in the SIL class, which is located in the Suomen ilmailuliitto’s building next to the SIL-shop. There will be two presentations – one about flying ultralight aircraft (for PPL-pilots) and another about water flying. The lectures are in Finnish so it may not be too useful for non-Finnish speaking people to come, but if there are Finnish readers who want to join, feel free. The event is free and available to everyone. There are people present from both MIK (Malmin Ilmailukerho) and MILK (Mäntsälän ilmailukerho), so if you want to meet representatives of either clubs, you are very welcome. Lecturers today are Ari Nikkinen / MILK (Mäntsälän ilmailukerho) and Tom Arppe / EUT (Experimental and Ultralight association).

MIK kerhoilta 4.3 Malmilla SIL-luokassa klo 18

Aihet:
1. Ultralentäminen moottorilentäjille (Ari Nikkinen / MILK)
2. Vesilentäminen (Tom Arppe)

Luentoiltaan on vapaa pääsy. Tervetuloa!

xorg.conf which works with nvidia-glx-177 on Intrepid and Lenovo T61p

A workmate asked what my xorg.conf contains. So here it comes:

karoliina@aurora:~$ more /etc/X11/xorg.conf
# nvidia-settings: X configuration file generated by nvidia-settings
# nvidia-settings: version 1.0 (buildd@rothera) Mon Oct 13 14:53:48 UTC 2008

# nvidia-xconfig: X configuration file generated by nvidia-xconfig
# nvidia-xconfig: version 1.0 (buildmeister@builder63) Wed Oct 1 15:09:35 PDT 2008

Section “ServerLayout”
Identifier “Layout0″
Screen 0 “Screen0″ 0 0
InputDevice “Keyboard0″ “CoreKeyboard”
InputDevice “Mouse0″ “CorePointer”
EndSection

Section “Files”
EndSection

Section “Module”
Load “dbe”
Load “extmod”
Load “type1″
Load “freetype”
Load “glx”
Load “dri”
EndSection

Section “ServerFlags”
Option “Xinerama” “0″
EndSection

Section “InputDevice”

# generated from default
Identifier “Mouse0″
Driver “mouse”
Option “Protocol” “auto”
Option “Device” “/dev/psaux”
Option “Emulate3Buttons” “no”
Option “ZAxisMapping” “4 5″
EndSection

Section “InputDevice”

# generated from default
Identifier “Keyboard0″
Driver “kbd”
EndSection

Section “Monitor”
Identifier “Monitor0″
VendorName “Unknown”
ModelName “IBM”
HorizSync 53.2 – 63.9
VertRefresh 50.0 – 60.0
Option “DPMS”
EndSection

Section “Device”
Identifier “Device0″
Driver “nvidia”
VendorName “NVIDIA Corporation”
BoardName “Quadro FX 570M”
EndSection

Section “Screen”
Identifier “Screen0″
Device “Device0″
Monitor “Monitor0″
DefaultDepth 24
Option “TwinView” “1″
Option “metamodes” “DFP-0: nvidia-auto-select +0+0, DFP-1: nvidia-auto-select +1680+0″
SubSection “Display”
Depth 24
EndSubSection
EndSection

Experiment: Falling into Jupiter ambient soundscape

Just a quick experiment on the ambient side. Ambient soundscape.
Try it out if you wish:
FallingIntoJupiter.mp3

The script goes like this:
- you are far away from Jupiter, approaching it on a trajectory which does not end up to a Jupiter orbit. Instead you are falling. There is nothing between you and the planet, and your speed is increasing and you can do nothing about it. And your headset pick the radiation interference as audio and you hear this thing. You fall between the clouds. Endless clouds in the huge atmosphere which feels like it never ends to a ground. Scary? Feel free to listen and have some ambient fun this time. This is very unusual to me, so please bear with me if it is not too perfect.

Creating MacOSX Qt project with qmake

It is not obvious and not clearly described in the qmake help, therefore I am typing what you need to do to here:

qmake -project
qmake -spec macx-g++ yourprojectname.pro

after that you can run:

qmake
make

(And your program is compiled)

You can now edit the pro -file as suits you best. To make it effect again, run qmake without parameters. If you encounter weird errors after changing the .pro -file, it might be because you have not run make clean. So after doing this, always run make clean before attempting to compile, otherwise you may get some headaches about issues that actually do not exist.

Maemo Summit 2008 video

Here is a video about Maemo Summit 2008. It features people attending the conference, C-base and Berlin and has my song “Big cat” as background music.

Maemo Summit 2008 from Karoliina Salminen on Vimeo.

NACA 66-020, 66-025, 66-030 body drag coefficient

Some numbers from Javafoil using the Drela approximation method (Xfoil after 1991):

NACA 66-020

Parameters: Length 6 meters, diameter from thickest point 1.2 meters:

α Re Cl Cd Cm 0.25 TU TL SU SL L/D A.C.
[°] [-] [-] [-] [-] [-] [-] [-] [-] [-] [-]
0.0 11.60E6 0.000 0.00709 -0.000 0.623 0.623 1.000 1.000 0.000 0.380

So estimated Cd for the fuselage is 0.00709. Doors, antennas, landing gear door, etc. will make it worse.

Bugs and dirt on the fuselage surface and the results becomes:

NACA 66-020

α Re Cl Cd Cm 0.25 TU TL SU SL L/D A.C.
[°] [-] [-] [-] [-] [-] [-] [-] [-] [-] [-]
0.0 11.60E6 0.000 0.01212 -0.000 0.625 0.625 1.000 1.000 0.000 0.380

NACA 66-030 (engine nacelle variant of the laminar body)

m/S = 1
α Re Cl Cd Cm 0.25 TU TL SU SL L/D A.C.
[°] [-] [-] [-] [-] [-] [-] [-] [-] [-] [-]
0.0 11.60E6 0.000 0.00775 -0.000 0.605 0.603 1.000 1.000 0.000 0.456

Cd = 0.00775

With NACA 66-025 the fuselage pod length drops to 4.8 meters.

NACA 66-025

m/S = 1
α Re Cl Cd Cm 0.25 TU TL SU SL L/D A.C.
[°] [-] [-] [-] [-] [-] [-] [-] [-] [-] [-]
0.0 9.28E6 0.000 0.00812 -0.000 0.612 0.612 1.000 1.000 0.000 0.417

Cd = 0.00818

Conclusion: All of these pods provide (according to simulation), a low drag coefficient.

Equivalent drag area for NACA 66-025 assuming body diameter of 1.2 meters:

0.00818*(0.6m*0.6m*3.14159) = 0.00925 m^2 (=0.0823 sq ft)

Hmm. did I calculate correctly? Somehow looks quite small.

NACA 66-020, 66-025, 66-030 body drag coefficient

Some numbers from Javafoil using the Drela approximation method (Xfoil after 1991):

NACA 66-020

Parameters: Length 6 meters, diameter from thickest point 1.2 meters:

α Re Cl Cd Cm 0.25 TU TL SU SL L/D A.C.
[°] [-] [-] [-] [-] [-] [-] [-] [-] [-] [-]
0.0 11.60E6 0.000 0.00709 -0.000 0.623 0.623 1.000 1.000 0.000 0.380

So estimated Cd for the fuselage is 0.00709. Doors, antennas, landing gear door, etc. will make it worse.

Bugs and dirt on the fuselage surface and the results becomes:

NACA 66-020

α Re Cl Cd Cm 0.25 TU TL SU SL L/D A.C.
[°] [-] [-] [-] [-] [-] [-] [-] [-] [-] [-]
0.0 11.60E6 0.000 0.01212 -0.000 0.625 0.625 1.000 1.000 0.000 0.380

NACA 66-030 (engine nacelle variant of the laminar body)

m/S = 1
α Re Cl Cd Cm 0.25 TU TL SU SL L/D A.C.
[°] [-] [-] [-] [-] [-] [-] [-] [-] [-] [-]
0.0 11.60E6 0.000 0.00775 -0.000 0.605 0.603 1.000 1.000 0.000 0.456

Cd = 0.00775

With NACA 66-025 the fuselage pod length drops to 4.8 meters.

NACA 66-025

m/S = 1
α Re Cl Cd Cm 0.25 TU TL SU SL L/D A.C.
[°] [-] [-] [-] [-] [-] [-] [-] [-] [-] [-]
0.0 9.28E6 0.000 0.00812 -0.000 0.612 0.612 1.000 1.000 0.000 0.417

Cd = 0.00818

Conclusion: All of these pods provide (according to simulation), a low drag coefficient.

Equivalent drag area for NACA 66-025 assuming body diameter of 1.2 meters:

0.00818*(0.6m*0.6m*3.14159) = 0.00925 m^2 (=0.0823 sq ft)

Hmm. did I calculate correctly? Somehow looks quite small.

Hello

This blog contains all my blogs in one.

Why I created this blog? Because I got treated badly in the Blogger service. My aircraft review blog was considered to be contain spam and obviously it was a false positive. I requested review to the blog, but no review has been so far done and my aircraft review blog remains locked. I am really unhappy to the very bad service of Google and hereby created this new blog, which also works as a backup to my postings, so Google don’t get them destroyed.

This is the message I got from the Blogger:

   Hello,

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Bad Google, bad!

Developing Qt Applications on Maemo

Kate Alhola’s and Antonio Aloisio’s presentation on Akademy 2008 about how to develop Qt Application on Maemo.

Developing Maemo Qt Applications from Karoliina Salminen on Vimeo.

Calculations from my Brussels trip (some spare time during sitting on the A320)

Calculations from my Brussels trip (some spare time during sitting on the A320)

Some calculations for plane which would utilize two HKS 700 turbos

I was flying today (as a passanger) to Brussels and I wasn’t doing nothing, I had paper, pen and the HP calculator with me. And of course J.D. Anderson’s Aircraft performance & design as a reference.

So I ended up with some numbers, but I know already that they are a bit off – since I calculated AR the other way around and got with the K and e I used AR = 10 even if I had chosen that the AR = 14. Therefore the climb performance may be even quite pessimistic. Besides of that I was reading yet another aerodynamics book which stated that e is as high as 0.9 for clean airplane.

However, numbers are: Trimaran configuration, 2 x HKS 700 turbo, 2 places, fuel 200 liters, S = 99 ft^2, MTOW 1980 lbs (maybe 900 kg would still be within limits, haven’t checked), AR = 14. Slotted flaps and flapped ailerons. Taper 0.5. Low drag laminar airfoil and 60% laminar fuselage shape and the plane will be quite fast. RG is assumed, gear stored in the pusher prop engine pods.

How to set up nVidia driver to Ubuntu Hardy on Lenovo T61p laptop

1. Download the latest nVidia driver from nVidia site. The driver should be 32 bit Linux (assuming you are running 32-bit version and not the AMD-64 -version), Quadro FX570M if you are running IBM T61p laptop. Otherwise (on other machines) select the appropriate display controller from the menu. Save the file to a location that you can easily access when you are in text mode (mandatory step).

2. Boot the Ubuntu (mandatory).
When the password dialog appears, press CTRL+ALT+F1
When text mode appears and asks for login, log in with your username and password.

3. Become root (mandatory):
sudo su
and then give your password

4. Stop the gdm (replace with kdm if you are running Kubuntu or kdm-kde4 if you are running Kubuntu-KDE4 remix)
/etc/init.d/gdm stop

5. If you don’t have compilation environment, you can install it by (optional):
apt-get update
apt-get install gcc g++ glibc

6. Uninstall now the nvidia open source driver (mandatory):
dpkg –purge xserver-xorg-video-all xserver-xorg-video-nvidia

Now you have no display driver installed on your system at all, you can’t start X.

Go to the directory where you have the nVidia driver package located.
It is named something like NVIDIA-something.run.
TYPE (mandatory):
chmod +x NVIDIA*.run

Now execute the package (mandatory):
./NVIDIA…..run (replace …. with the correct filename which depends on which driver version you have).

Accept license agreement.
Answer to the question if the installer wants to download precompiled kernel module from nVidia site that “No”.
It may state that you have already a nVidia driver installed and if you want to uninstall the driver first. Answer yes to that kind of question.
The installer asks also if you want to modify the xorg.conf for the driver. Answer yes to that kind of question.
Your new driver is now successfully installed if you didn’t receive any errors in the process.

You can now restart the gdm to log in the system without rebooting:
/etc/init.d/gdm restart

If you are using external display in addition to the laptop screen, you may need to reboot to get it functioning correctly. You need to have both the external display and laptop display turned on when you boot the computer for the nVidia driver to autoconfigure it properly.

If your display settings still aren’t correct, you can edit them with nvidia-settings (optional):
Open terminal window
sudo nvidia-settings

Change the settings to appropriate and save to xorg.conf. Please note that you may need to run the nvidia-settings from terminal window instead of clicking the icon or menu item which launches nvidia-settings because in order to write to the xorg.conf you need to be root and Ubuntu wasn’t designed to support the nVidia settings application as it has its own (but sometimes not working) installers for binary drivers (the envy package which may work for some, but at least didn’t work for me with IBM T61p and Hardy).

Aircraft calculator web page

I found this:

http://anton.panchishin.com/docs/aircraftcalc.html

I am not sure how useful it is, but just for fun, enjoy.