From Lake Yamanaka to Narita airport

Hi, I will be staying around Lake Yamanaka in the Fuji area, namely in Yamanashi in October. From there, I will be travelling to Okinawa on the 17th, and my flight is scheduled to depart at 14.50. What time do you think I need to leave in order to get to the airport in time? What is the best suggested route? I looked online a lot for one, and I am really not sure. Thanks

I recommend you to leave very early. it depends on how far you stay from the large station but the access between Yamanashi and Tokyo is not good, moreover the access to Narita from Central tokyo is little bit bad.

If you can go to Fuji Station in Shizuoka pref you can take Shinkansen that takes about 1.5 hours to get to Tokyo station.

Shinkansen trains run via Shin-Fuji Station, not via Fuji Station.
And, you don�ft need to travel via Shizuoka Prefecture to get from Yamanakako to Narita International Airport [NRT].

- japan-guide.com: Lake Yamanakako: Access
http://www.japan-guide.com/e/e6908.html#jump_access

What time do you think I need to leave in order to get to the airport in time?

Where around the lake is your accommodation? Do you know a bus stop located nearby?

I recommend you travel early to the airport for a case where the transportations happen to be delayed.
If you can catch the highway bus #1104 (for Shinjuku Expressway Bus terminal) scheduled to depart around 08:25 - 08:40 from bus stops along the lake, you can get to the station in your NRT terminal by 13:20.

I will be travelling to Okinawa on the 17th, and my flight is scheduled to depart at 14.50.

Your flight is Vanilla Air #805 to Naha Airport, right? If so, your terminal is NRT Terminal 2 and you need to check in by 30 minutes before the departure time, i.e. by 14:20. (NRT-bound trains make a stop at the station in Terminal 2 just before arriving to Narita Airport Station in Terminal 2.)

If your Vanilla Air fare type is Inclusive, it is worth considering flying instead from Tokyo International Airport [HND, Haneda Airport] by JAL or ANA with a discount air ticket. (NRT is located actually outside Tokyo Metropolis and much further than HND from Yamanakako.)
- japan-guide.com: Discount Air Tickets
http://www.japan-guide.com/e/e2364.html

(1) Highway bus #1104
(Regular cost: 2100 yen per adult from Yamanakako Hirano)
: Yamanakako Hirano {8:25} ---- Bugakusou-mae {8:28} ----
Yamanakako Asahigaoka {8:35} ---- Yamanakako yakuba-mae {8:37} ----
Yamanaka-kyoku-iriguchi {8:38} ---- Fujisan Yamanakako {8:40} ----
Kawaguchiko Station {9:10} --//-- {10:55} Shinjuku Expressway Bus terminal.

(2a) JR Ltd. Express Narita Express 23
(Regular cost: 3190 yen per adult with a seat reserved)
: Shinjuku : Track 5 {11:40} --[JR]-- {12:54} Airport Terminal 2.

(2b) JR non-express train and Keisei non-liner trains
(Regular cost: 1440 yen per adult with a seat reserved)
: Shinjuku: Track 15 {11:48} --[JR]--
{12:09} Nippori: the transfer gate: Nippori {12:18} --[Keisei: Limited Express]--
{12:31} (Keisei) Takasago (via the same platform) {12:32} --[Keisei: Access Express]--
{13:14} (Narita) Airport Terminal 2.

A typing mistake is found in my previous message.
NOT: Narita Airport Station in Terminal 2.
BUT: Narita Airport Station in Terminal 1.