Oxygen in Piper Seneca V?

I'm not sure that just filling the fuselage with oxygen at that altitude will help. When you reach a certain altitude, Diffuse Cerebral Hypoxia (DCH) sets in, where the pressure differential between the surrounding air and the blood, stops blood being oxygenated, but into a mask, it might be more beneficial. It might well be equipped with cabin pressurisation in the real world, or the manufacturers didn't think there was a need for the pressurisation (its expensive and complex)

😉

The Seneca V is not pressurized, many light twins are not. It all comes down to money and weight. To pressurize a model of aircraft requires re-engineering, recertification and additional hardware(weight). The aircraft will lose cargo capacity, climb rate, cruise speed and service ceiling because of the extra hardware and reinforced structure. The engine size sometimes has to be increased, it's almost like starting all over with the design. If the aircraft can only fly at FL 180 then the time and extra money is not worth it to the company nor to the aircraft buyer.

You can't just release oxygen into the cabin of a unpressurized aircraft, it would do nothing to increase the O2 saturation of the occupants blood. Wearing a O2 mask is a safe and financially viable way of operating the aircraft at the 12,000-18,000 foot altitudes without the cost as stated above. Equipping a light twin with a built in O2 system is an option that the aircraft buyer can choose if they would like. Some choose to save the money and fly with a portable system that can be carried in different aircraft, they may only need to fly at the stated altitudes only occasionally. Some don't need to fly at those altitudes at all so declining the option allows a lower purchase price for the aircraft. 🙂

what is the difference between using a mask and filling oxygen into the cabin?

nottobe wrote:

what is the difference between using a mask and filling oxygen into the cabin?

If you just release it into the cabin it will vent to the outside and you never achieve a high enough concentration to be effective. The mask basically lets you send it staight to the lungs. It just is not worth it to pressurize light GA aircraft. Usually when they have been made they are poor sellers. The GA buyer is not willing to pay the added cost, complexity, and performance hit that pressurizing a light twin, or single, entails.

so in Seneca V the oxygen valve is only for plugging in the masks?
I am sure Seneca V has the oxygen switch.....

Yes, a built in oxygen system is an option ($9,190). 🙂

http://www.piper.com/pages/SenecaPriceStandardEquipment.cfm

ok, I would like to know: is this oxygen sytem designed for oxygen mask plug-in only, including passenger masks?

Yes, it will have outlets for all occupants. You can use a mask or cannula. The cannula fits directly into the nostrils and is lighter but the cannula is only certified to 18,000 ft. The constant flow mask can be used up to a altitude of about 28,000 ft. There are different types of mask that are good to higher altitudes. The mask is equipped with a microphone for communication. The system utilizes a single tank that is refilled at some airports, I don't know the price but nothing in aviation is cheap. Duration depends on number of consumers and altitude of use but it should last two people about 12 hours of use, more with the cannula. 🙂

http://www.aerox.com/