Ram air

[The-sky-captain]

What are you guys thoughts on the Mooney ram air system? I've got a 77 J and notice only about a 1/2"  or so when it is on so I generally don't use it. I don't really see any difference with it on or off.

[KSMooniac]

I see no measurable difference on my '77 J and never use it.  In fact it was completely deleted on the later model J's and there is a kit available to do so for our planes.  As I found out a few weeks ago, the deletion kit is *much* cheaper than the rubber seal between the ram air ring and the cowl!  Before I paint my plane I will either apply the kit (needs to be painted after installation) or switch to a LoPresti cowl that retains ram air and makes it effective.

The Pre-J planes I flew (a couple F's and and E) it was good for a solid 1" of MP when used, though.

[Rustler]

I've got a new-to-me '80 J and see little or no difference opening the ram air. I don't bother to use it.

I'm about to make a trio from Texas to South Carolina and Tennessee and intend to use some of the idle time to try to determine whether it is my imagination or not.

[The-sky-captain]

The flush plug does sound like it would be an easy fix to the problem. Wonder why there isn't a mod out there for it?

[GeorgePerry]

I guess I'm the exception but I get a full 1 in of MP boost with it on.  Also a noticable change in EGTs between open and closed.  I use it, for what that's worth,

 

I HATE MICROSOFT!!!!  The sooner the world embraces MAC's the better.  Sorry for the tripple post

[Cruiser]

the biggest thing I noticed about Ram air was the annunciator light kept coming on during short final. It was very irritating. Had to have the cable adjusted. I have used it without any noticeable improvements.

[Piloto]

Although not very effective it can be useful for determining air filter replacement. If you get more than 1/2" difference on MP it is time to replace the air filter.

José

 

[m20j]

With a digital MP gage on a '77 201, it is good for .2 to .3 inches with a corresponding increase in fuel burn.  I can't see the analog gage move at all.

I use it at altitude on long flights for a little extra oomph, but not for short hops.

[hansel]

We had the ram closure kit on our '79 J at purchase but the cowling fiberglass work was never completed. The lower cowl had some unrelated heat damage develop over the years that we recently decided to fix, so it seemed like the right time to finally plug the blow hole. A pretty painless process overall (about $700). Pics attached. I'm expecting improved aerodynamics to add at least 10mph to my airspeed (j/k)

 

[The-sky-captain]

Quote: KSMooniac

I see no measurable difference on my '77 J and never use it.  In fact it was completely deleted on the later model J's and there is a kit available to do so for our planes.  As I found out a few weeks ago, the deletion kit is *much* cheaper than the rubber seal between the ram air ring and the cowl!  Before I paint my plane I will either apply the kit (needs to be painted after installation) or switch to a LoPresti cowl that retains ram air and makes it effective.

The Pre-J planes I flew (a couple F's and and E) it was good for a solid 1" of MP when used, though.

[Immelman]

Ram air makes a solid 1" rise in MP on my E model, and a notiable performance boost. Anytime I'm going someplace (not a local 'slow' flight) its on as long as the atmosphere permits, until descent.

[Piloto]

Hansel your ram air mod looks beautiful and professional. You probably get more speed now (less drag) than when it was used before. Thanks for the pictures

José

 

[KSMooniac]

Bodie, yes I deleted my ram air system when I had the plane painted.  The shop filled in the cowling hole prior to paint, so it looks like it was never there.  Back home, I removed the rest of the system and riveted a close-out panel onto the induction box where the ram air intake used to reside.  Simple task, but it took a long time to R&R everything since the air box had to come off the plane to rivet the plate with regular "smash" rivets.  Apparently you're not supposed to use blind rivets on induction components.  Removing the ram air cable + microswitch assy was a PITA due to tight access under the panel, as usual.

[231Pilot]

I do not use it.  Bugs and other junk can be found in the air at RAM AIR altitudes.  Not a good thing.  I want clean, filtered air going into my precious bird.

[rogerl]

Spent the last few days at Doña Ana (5T6) - a couple more than planned.  Friday 55/60 mph wind/sand storm popped up, and by the time we got to the airport, conditions were too bad to move zt from the tiedown into the hanger.  Fortunately for the structure -  but unfortunately for the ram air door - it was pointed into the wind.

The ram air door doesn't close super tightly - even though the gasket is reasonably pliable.  Sand/dust had an hour or so to infiltrate before we got to it to duct tape over the door.  Saturday was spent removing the cowling and the ram air butterfly valve and carefully sponging out debris.  Fortunate that the throttle was fully closed, leaving that horizontal butteryfly valve as a further obstacle to ingress.

The return trip Sunday was uneventful, so seems that any damage is more chronic than acute.  An A&P/IA that was around did note that he wouldn't worry about it, as most would blow through the engine at startup - but I did my best to get every speck I could find out, + am going to do an oil and filter change ASAP.

Lessons learned:

1) Hanger it if there's a reasonable option; or at least be vigilant about the weather when on a trip even while NOT flying

2) Cover and delete the ram air system ASAP

Side note: 5T6 FBO operator "Blue Feather Aviation" took great care of us - I highly recommend paying a visit if you have a chance.  Don't miss war eagles air museum (http://www.war-eagles-air-museum.com) on the field.

[kallend]

Quote: KSMooniac

 

The Pre-J planes I flew (a couple F's and and E) it was good for a solid 1" of MP when used, though.

[Stefanovm]

I have a slightly different problem with my ram air. When I picked my 65 E model up two months ago, I noticed that the flap was not closed. Every time I tried to close it the cable housing just backed out of the last clamp. Therefore, I do not use it. It does not seem to come open if I do not touch the control and have forced it closed (left photo). However, if I open it with the control (right photo), I have to close it later by removing the side cowling and forcing the outer cable and actuator arm to move forward. This is very hard to do in the tight conditions. I took photos through oil cooler opening. I tried to see if I could find a better way to anchor the outer cable and the oil cooler is not normally out of the way when I force it closed in very tight conditions. My A&P did not seem to know what would be an "official" repair.

I know it needs work. Any suggestions for central Texas? San Marcos probably.

The door gasket also appears to be in pretty bad shape and should also be replaced. I am sure stuff that should not be getiing into the system may be doing so around the gasket.

It does stay in a hanger, but I fly from a grass strip. Infiltration worries me. I wonder if it is not staying closed even though the control is firmly against the panel. However, when back on the ground it seems closed by looking unless I have accidentally pulled the control after the last hand closure from the engine compartment. Again it also needs a new gasket or door. I am contemplating a temporary plug using expaning foam.

[scottfromiowa]

I use my Ram Air ALL THE TIME IN CRUISE, unless down low where I am not at full throttle and get 25 inches without the Ram-Air.  I get a nice boost on my '66 E.  Make sure the gasket is functional and don't open down low or in moisture.  End of story.  The lite is a nice reminder...as well as my decent checklist...I have no fear of a phantom grasshopper at 7500 feet.

[Mooney65E]

I use mine over 5000' in clear air only and see 1" plus MP increase. Take very good care of the boot which connects the door to the cowling during removal of lower cowling. They are EXPENSIVE!

[Ned Gravel]

Quote: Mooney65E

I use mine over 5000' in clear air only and see 1" plus MP increase. Take very good care of the boot which connects the door to the cowling during removal of lower cowling. They are EXPENSIVE!

[Mcstealth]

Quote: Stefanovm

I have a slightly different problem with my ram air. When I picked my 65 E model up two months ago, I noticed that the flap was not closed. Every time I tried to close it the cable housing just backed out of the last clamp. Therefore, I do not use it. It does not seem to come open if I do not touch the control and have forced it closed (left photo). However, if I open it with the control (right photo), I have to close it later by removing the side cowling and forcing the outer cable and actuator arm to move forward. This is very hard to do in the tight conditions. I took photos through oil cooler opening. I tried to see if I could find a better way to anchor the outer cable and the oil cooler is not normally out of the way when I force it closed in very tight conditions. My A&P did not seem to know what would be an "official" repair.

I know it needs work. Any suggestions for central Texas? San Marcos probably.

The door gasket also appears to be in pretty bad shape and should also be replaced. I am sure stuff that should not be getiing into the system may be doing so around the gasket.

It does stay in a hanger, but I fly from a grass strip. Infiltration worries me. I wonder if it is not staying closed even though the control is firmly against the panel. However, when back on the ground it seems closed by looking unless I have accidentally pulled the control after the last hand closure from the engine compartment. Again it also needs a new gasket or door. I am contemplating a temporary plug using expaning foam.

[Stefanovm]

Not yet. Thanks.

[N201MKTurbo]

Stefanovm

You should not use a cushoned clamp for the cable. You will never get it stop slipping. Rig the cable about 1/4 inch through the clamp, then wrap about two turns of lock wire around the end of the cable sheath, twist it tight for the length of the clamp then wrap a few more turns around the cable on the other side of the clamp and twist the loose ends. Another option would be to get some of the boden cable nuts that are used on the Mooneys with the Dukes gear actuator for the emergency engagement cable and put two nuts on either side of the cable.

[N201MKTurbo]

Stefanovm

You are also missing a clamp. There should be a second clanp held on by a spacer and bolt that goes through the empty hole in the middle of your second photo.

[Mcstealth]

Quote: Stefanovm

Not yet. Thanks.