Thicker ¼" Glass & Windshield STC Mods and Whisper Soundproofing Packages

Through our research over the last 25 years, we have developed effective methods and modifications to reduce the sound transmission level or perceived decibel noise level in M20 Mooneys to the pilot and co-pilot by some 4-6 db.

Doesn't sound like much you say? Let me put it another way. Typically in most all GA aircraft and including most Mooneys, or at least the ones prior to the current production models (fitted with the composite interiors), normal conversation and true acceptable noise ambiance was strained-at best. In fact, most audio experts consider hearing protection or ANR headsets to be an absolute necessity for prolonged use and/or to assist in communication with ATC. Even with electronic ANR headsets, the excessive cabin din still has adverse affects on your body to the point of it causing (what the FAA terms) Flight Fatigue.

New Style One Piece Curved Current Production (M20J/K/M/R etc.)
1/4" thick Side Glass Up-Grade
1/4" and 3/8" Windshield Up-Grades
Oversize Pilot's Vent Window Up-Grade
Applicable For Older Pre-201 M20s as well as M20J/Ks And On)

Our STC'd 1/4" and optional 3/8" thick M20J/K Concave OEM style windshields make a significant if not un-believable difference in the overall ambiance of the Mooney operating experience. Besides adding some 2-3 MPH in cruise, installing the compound curved newer style windshield is perhaps the single most important item you can do to aid in quieting the din of your older Mooney.

1/4" and 3/8" Thick Windshield Up-Grades For Newer M20J & Up M20s

Even if you own a newer style M20J/201, 231, 252, or even a, Ovation/TLS etc., our ¼" & 3/8" thicker Windshields and Side Glass Mods will make a definite difference in cabin sound levels as well as add a certain measure of protection for the always present bird strike possibility.

Mooney Sound Proofing Sound Deadening Factoid

Make no mistake about it, the M20 Mooney cabin structure is different than most contemporary designs. Unlike Brand, B, C, or P, the M20 fuselage is not monocoque (stressed aluminum skin) constructed like nearly all aluminum skinned GA aircraft. The M20 fuselage is more akin to the rag and tube construction common to today's acrobatic biplanes as it has the stronger triangulated 4130 steel tube fuselage tubes to carry the aerodynamic loads. Consequently, the M20's outside cabin skin is only there to keep the wind and rain off the pilot and passengers- so to speak! This means the largely slab sided cabin skin is far looser or less stiff than most conventionally designed GA aluminum aircraft, and consequently the cabin skins tend to pulsate/vibrate in harmony with the blasts from the prop blade passages.

Anything (like thicker or stiffer glass) which can stiffen up the cabin skin assists in keeping the noise transmission down. Think of it like sitting inside a kettle drum!

Our research has shown that our specially designed thick side glass goes a long way to stiffen the entire M20's cabin skin structure, and thus greatly assists in reducing the noise transmission level far more than installing thicker glass in normal GA aircraft.

1/4" Thick Side Glass Up-Grade/Mod

This mod is one of the most popular we have ever introduced! It replaces your old 1/8" thick (so thin as to be actually flimsy) side glass with the far stiffer 1/4 glass. This mod is vital in our soundproofing process and strongly recommended to virtually every Mooney owner in his quest for an acceptable and hearing safe cabin ambiance.

Our Thicker Glass Mods are available for every model M20 in styles or tints. Clear, and the current production popular Smoke Tint.We strongly recommend you chooseSmoke Tint as it is a mild tint that is better for low light/night ops as most mistake even for clear, but still the same, it still offers some protection from the sun.

See our Modifications and Maintenance Sections and our 107MM Mod Section for more information and pricing.

#107MM: NEW 1/4" SIDE GLASS: Installed on M20J/K (or newer) $3,495 to $3,895*
*If done along with a new interior or similar, $4,195 if done on a stand alone basis.

#102MM: M20J/201/252 1/4" Thick Factory M20J/K OEM Windshield Up-grade/Mod On Older Pre-201 Type Mooney M20C/E/F's etc. $6,495.00*
Using OEM Factory Cowl Deck, Retainers, & Doublers etc. And includes Tinted 1/4" Glass. May be installed w/out Retainers & Doublers for approximately $5,695
*Call for specific details and exact price on your Pre-201 prior to booking

#106MMA Install Double Thick 3/8" Windshield Glass (only) On M20J/K & On etc. $3,495+/-*
*Notes: Standard OEM stock thickness is 3/16th. Price stated is with us re-using your old retainer bow assembly New bow assembly is extra.

#106MMA Install 1/4" Thick Windshield Glass On M20J/K etc. $2,695 To $3,696*
Frankly, we think we are better at this mod than anyone else!
*Notes: Over the years Mooney used different sealing compounds between the glass and fuselage skins. Depending on which compound was used, the labor to remove the old glass can vary significantly. Normally, we can't determine exact labor until we examine the individual Mooney.
Standard OEM stock thickness is 3/16th. Price stated is with us re-using your old retainer bow assembly New bow assembly is priced extra.

M20C,E & F's Side Glass w/flush screw attachments (includes new SS screws) $3,595 To $3,995*
Price varies depending on the kind of sealant used on pre-existing glass, and/or if done along with (at the same time as) a new interior or similar associated work.

Popular Glass Mod Options:

1 Piece Picture Window Mod for M20F's (Additional) +$1,995+/-

side vent

Optional Oversize Pilots Cabin Vent Window Mod (see below) $895
Great for more ventilation while on ground and for taking photos etc. We think this is the size this vent should have been from the get-go.

Super Size (Bonanza style) Oversize M20 Pilots Vent Window Mod Mooneys are known for their claustrophobic teenie weenie pilots vent windows. Now you can have a more normal size vent perfect for photography as well as one which will provide more ventilation and comfort while on the ground!

Original Stock Window VS Super Size Note the original stock size vent window (being held) in comparison to the Oversize M20 Vent Window w/new 1/4" Side Glass.

Available as an option for all M20's w/our 1/4" Glass Mod $675
(If done while 1/4" Side Glass is being installed)

MSE/252/205/TLS Style Rounded Window Mod for all model M20's (Additional, over any other charges) +$995

In short, when considering the minimal weight difference and expense (compared to stock 1/8" thin & flimsy glass), and considering the advantages, we feel there is no reason ever to allow stock glass to remain in your Mooney!

Click Here For More Information On Our 1/4" Side Glass Mods.
Click Here For More Information On Our OEM Factory M20J/201 Windshield Mods For Older Mooneys.
Click Here For More Information On Our Whisper Soundproofing Mods.
Click Here for a partial re-print of a research article in Aviation Consumer Magazine for more details about the benefits of installing 1/4" glass in a Mooney airframe.