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Author Topic: Clamshell Doors  (Read 224 times)

seanmcgillivray

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Clamshell Doors
« on: September 25, 2021, 07:48:14 am »
While I was out at EAC last week for the their MX training I learned about the clamshell door removal STC. I then started to notice more than a few plans that had the doors removed.

Guess looking for a show of hands to see who has removed them, why and what if any performance loss they experienced.

donv

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Re: Clamshell Doors
« Reply #1 on: September 25, 2021, 12:16:16 pm »
I have clamshell doors on my 980, but I used to fly a bunch of 690s which had them removed. I can't say I could tell the difference in speed, as I never had a chance to directly compare, but I do know there were some maintenance issues (cracking) in the rear part of the nacelle after a few years.

I chose to keep mine on, and so far I've been very happy with the decision.

Steve binnette

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Re: Clamshell Doors
« Reply #2 on: September 25, 2021, 12:27:22 pm »
I went the other way.  My airplane did not have gear doors on it when I bought it. I had the doors reinstalled on my airplane.  I flew it for two years without the doors.

It just looked like the lack of doors had to cause drag and turbulence.  The wheels sit pretty deeply into the wheel well leaving an obvious source of drag and potential cracking on the wheel well cowl.

I know on 421ís by adding hub caps you can get improved climb and cruise performance.  It seemed adding the gear doors back would help the commander.

The only down side was possible MX cost.  So far no issues with the doors.

I had tracked performance before and after.  The doors added 300fpm in climb and 5kts in cruise.  They also lessened the vibration noticeably.  On the first flight I could feel the reduced vibration through the floor.  It was like when I upgraded my props on my 421. 

I also like having the plane as close to factory condition as is possible.  Was it worth it?  It was for me but  probably not for everybody..  The cost was $20k, but I also like the way they look.

I would not remove them if I had them but 20k is a lot for the improvement gains.


Adam Frisch

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Re: Clamshell Doors
« Reply #3 on: September 25, 2021, 01:17:38 pm »
I removed mine just to have less hydraulic actuators and linkage, but I think if I had a faster -10 I would just keep them, like Steve has done. Not sure the removal is worth it.
Slumming it in the turboprop world - so you don't have to.

seanmcgillivray

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Re: Clamshell Doors
« Reply #4 on: September 26, 2021, 07:30:20 am »
I am not planning on removing them and prepared to maintain them.

Just was a little surprised how many Commanders had them pulled off. I am with Steve, they have to have a performance cost.

schrambow

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Re: Clamshell Doors
« Reply #5 on: September 27, 2021, 11:01:22 am »
our 681 we had came with the gear doors off.   We found a pair on Ebay for $600 bucks back in the day, and put them on.  The passengers in the back noticed a pretty big different in sound when comparing it back to back.  (less vibration and less noise for sure).  Performance was also improved like stated above.  A little bit more maintenance with sequencing valves, etc...   but it worth it i believe with all the benefits gained.  My opinion anyway.

kent4142

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Re: Clamshell Doors
« Reply #6 on: October 18, 2021, 08:27:59 pm »
Soooo, you are saying you "might be under water, shelling out so many clams for the doors, but ya'll can se"a" your way to dipping into the well for the speed and beauty?   ;)

schrambow

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Re: Clamshell Doors
« Reply #7 on: October 18, 2021, 09:10:37 pm »
"K",  when can we get some photos of that nice new panel and/or your overall experience with all that new glass in your cockpit?

kent4142

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Re: Clamshell Doors
« Reply #8 on: October 19, 2021, 06:45:06 pm »
Okay Okay - here is a photo.   :D

I thought long and hard about "pimping out" our 81 Cessna 414A, but at long last, I decided when it was all said and done, I would still have a 414.

Pimping out the Commander is waaaay more fun, and when I am done pimping the Commander - I have got an incredible machine for traveling. 

On any given trip, I spend less money on fuel in the Commander than I did with the 414, sooooo with all that money I am saving I am putting the money into the panel of the Commander!!!   :D :D ;D

On the trip to Maine from Florida (non stop in under 4 hours), the GTN 750 lets me fly waypoints and airways - this is super helpful in the North East.  The GTN 530 that I flew, did not have that capability.  The satellite weather is absolutely the bees knees.  Traffic, Graphic turbulence forecast (I have learned - this is a big deal above 19,000 in the Commander), winds, destination weather, xm rain composites . . . . as well as about a million other features available in the cockpit.

Digital radar available on the G600 txi or the 750 - a nice feature when I want to see everything.  We have to deal with thunderstorms almost everyday here in FL in the summer.  In general having multiple screens is very very wonderful, other than radar and xm, when doing approaches I can display the approach waypoints during the approach in flight plan mode (matrix style) so I can see distances and times to each fix all the way to the runway, and still show the map view with the synthetic window on another screen.

Oh, and here is a big big huge benefit;  On a long multi-leg trip like my trip to Maine - I don't have to lift up my big fat heavy arm, and and turn the OBS knob to the next waypoint anymore. The GPSS and the G600 automatically fly the route because the OBS updates automatically.  The steam gauges and my old GPSS didn't do that.  (Actually my old GPSS didn't even work).  If I didn't have to talk to ATC all the time I could nap!!  (That is a joke!).

I haven't figured everything out with the G600 yet.  Lots and lots and lots of options, but I truly believe I have increased my single pilot IFR safety.

Yes, it all costs a lot of $$$$.  Is it worth it?  How can I say.  I used to figure, all in, the Cessna 414 was costing us about $85,000 per year to fly 125 ish hours per year.  That is allowing for every cost related to the airplane, engine replacement, avionics upgrades, new paint some day, fuel, insurance, down to washing the outside and air freshener.  I estimate the Commander at about $130,000 per year give or take long term.  If you amortize the costs of upgrades over the total ownership cost - it sort of averages out.  At least that is how I have been convincing myself it is worth it.

It is a business expense #1, and #2, my two sons are now in the business, and they both fly.  In fact they just got their initial training in the Commander last month.!  (Talk about scary!!!!).  But I digress, I want them to be as safe as possible - not to mention I want that for myself.  I truly believe all this technology makes our flying safer.  So that is my story, and I am sticking to it.

kent4142

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Re: Clamshell Doors
« Reply #9 on: October 19, 2021, 06:57:09 pm »
Here is another photo.

kent4142

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Re: Clamshell Doors
« Reply #10 on: October 19, 2021, 07:00:09 pm »
One more try

donv

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Re: Clamshell Doors
« Reply #11 on: October 19, 2021, 09:15:12 pm »
Fantastic looking panel! And I couldn't agree more about the benefits.

schrambow

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Re: Clamshell Doors
« Reply #12 on: October 19, 2021, 09:39:41 pm »
Thanks for sharing Kent!  It looks awesome!  Glad you like it all.  When doing our first hot inspection in 200 plus hours, i am thinking of installing the G600TXI also while it is down.  You happy with the new onboard radar rather than the old unit that was in it?  I got old people around me, yelling at me to keep the old radar and not go with the new Garmin radar due to using 750 for nav instead of weather pages, etc..  old people i guess.  But if I go with G600TXI, I will have to remove the old radar for that space/panel issues anyway. 
If you pull your power levers back to suck about 210 lbs/side at that altitude, you can pretend you are in a -5 machine then and not be so close to that barber pole in cruise!

 

donv

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Re: Clamshell Doors
« Reply #13 on: October 19, 2021, 09:49:19 pm »
I have the Garmin radar. I was a bit concerned about using the screen space on the 750 to view it, but given the view I have from Garmin Pilot on the iPad as well, it works pretty well. The radar is supposed to display on the G600 as well, but I need to get that properly set up. Once that's done, I think it will be really nice.

So all in all, I like the Garmin radar.

Adam Frisch

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Re: Clamshell Doors
« Reply #14 on: October 20, 2021, 06:05:36 am »
Killer panel, Kent! Reminds me of Steve Binnette's 980 panel. Great stuff, so jelly!  :)
Slumming it in the turboprop world - so you don't have to.