ARRIVAL AND ENTRY

There are six major airports in Madagascar, including the two international airports in Antananarivo (TNR) and Nosy Be (NOS).
Mahajanga, Tamatave, Tulear, and Diego are the 4 others.
The airports in Fianarantsoa, Fort Dauphin, Manakara and St. Marie are also still paved but not that big.
Madagascar Airlines is the national airline. Domestically this is now called Tsaradia. The following airlines currently fly to Madagascar.

From Europe to Antananarivo (TNR):

Air France from Paris CDG and Marseille, 

Feeders via all major European airports.

Kenya Airways via Nairobi

Air Äthiopien via Addis Abebba

Air Mauritius via Port Louis

Air Austral via Saint-Denis , La Reunion

Madagascar Airlines (no flights operating at the moment)

Corsairfly from Paris Orly

Southafrican Airways (Fly Airlink) via Johannesburg

Turkish Airlines via Istanbul and Stopover in Port Louis

From Europe to Nosy Be (NOS):

Neos Air from Milan, Verona via Rome direct to Nosy Be

Air Äthiopien via Addis Abebba to Nosy Be (from Europe Major Airports)

Visa:

All visitors to Madagascar require a visa. You can pay and receive a visa directly upon arrival at the airport for stays from 30 days up to 60 or 90 days.

A passport valid for six months from the date of entry is required.
At least the short stay visa is required approx. 35 euros (for 30 days).
Make sure your passport has an entry stamp. A tourist visa has a maximum validity of 3 months and cannot be extended.
Sometimes the authorities require a printed copy of the e-ticket, if you don't have one you can be turned away. You must also be able to show a return ticket.
Since January 1, 2016, every foreign tourist has to pay a tourist tax of €10.