Petit probleme avec la update

Bonjour,
je suis entrain de créer des page dans mon site pour des mise a jour ou modification ,mais sa ne veux pas marcher je ne sais pas pour quoi je vous passe le code et je ne comprends pas d'ou vient le problème du php ou du sql
j'ai deux pages une formulaire qui envoie les valeur a une autre page pour exécuter les requêtes voila les code
1)le formulaire

<?php
if(isset($_GET['status']) && $_GET['status'] == "success"){
echo "Ajout reussi";
}


?>
<style type="text/css">
<!--
.Style1 {color: #FFFFFF}
.Style2 {color: #999999}
.Style3 {color: #655F48}
-->
</style>

<table class="ds_box" cellpadding="0" cellspacing="0" id="ds_conclass" style="display: none;">
<tr><td id="ds_calclass">
</td></tr>
</table>
<script type="text/javascript">
// <!-- <![CDATA[

// Project: Dynamic Date Selector (DtTvB) - 2006-03-16
// Script featured on JavaScript Kit- http://www.javascriptkit.com
// Code begin...
// Set the initial date.
var ds_i_date = new Date();
ds_c_month = ds_i_date.getMonth() + 1;
ds_c_year = ds_i_date.getFullYear();

// Get Element By Id
function ds_getel(id) {
	return document.getElementById(id);
}

// Get the left and the top of the element.
function ds_getleft(el) {
	var tmp = el.offsetLeft;
	el = el.offsetParent
	while(el) {
		tmp += el.offsetLeft;
		el = el.offsetParent;
	}
	return tmp;
}
function ds_gettop(el) {
	var tmp = el.offsetTop;
	el = el.offsetParent
	while(el) {
		tmp += el.offsetTop;
		el = el.offsetParent;
	}
	return tmp;
}

// Output Element
var ds_oe = ds_getel('ds_calclass');
// Container
var ds_ce = ds_getel('ds_conclass');

// Output Buffering
var ds_ob = ''; 
function ds_ob_clean() {
	ds_ob = '';
}
function ds_ob_flush() {
	ds_oe.innerHTML = ds_ob;
	ds_ob_clean();
}
function ds_echo(t) {
	ds_ob += t;
}

var ds_element; // Text Element...

var ds_monthnames = [
'Janvier', 'Février', 'Mars', 'Avril', 'Mai', 'Juin',
'Juillet', 'Aout', 'Septembre', 'Octobre', 'Novembre', 'Décembre'
]; // You can translate it for your language.

var ds_daynames = [
'Dim', 'Lun', 'Mar', 'Me', 'Jeu', 'Ven', 'Sam'
]; // You can translate it for your language.

// Calendar template
function ds_template_main_above(t) {
	return '<table cellpadding="3" cellspacing="1" class="ds_tbl">'
	     + '<tr>'
		 + '<td class="ds_head" style="cursor: pointer" onclick="ds_py();"><<</td>'
		 + '<td class="ds_head" style="cursor: pointer" onclick="ds_pm();"><</td>'
		 + '<td class="ds_head" style="cursor: pointer" onclick="ds_hi();" colspan="3">[Fermer]</td>'
		 + '<td class="ds_head" style="cursor: pointer" onclick="ds_nm();">></td>'
		 + '<td class="ds_head" style="cursor: pointer" onclick="ds_ny();">>></td>'
		 + '</tr>'
	     + '<tr>'
		 + '<td colspan="7" class="ds_head">' + t + '</td>'
		 + '</tr>'
		 + '<tr>';
}

function ds_template_day_row(t) {
	return '<td class="ds_subhead">' + t + '</td>';
	// Define width in CSS, XHTML 1.0 Strict doesn't have width property for it.
}

function ds_template_new_week() {
	return '</tr><tr>';
}

function ds_template_blank_cell(colspan) {
	return '<td colspan="' + colspan + '"></td>'
}

function ds_template_day(d, m, y) {
	return '<td class="ds_cell" onclick="ds_onclick(' + d + ',' + m + ',' + y + ')">' + d + '</td>';
	// Define width the day row.
}

function ds_template_main_below() {
	return '</tr>'
	     + '</table>';
}

// This one draws calendar...
function ds_draw_calendar(m, y) {
	// First clean the output buffer.
	ds_ob_clean();
	// Here we go, do the header
	ds_echo (ds_template_main_above(ds_monthnames[m - 1] + ' ' + y));
	for (i = 0; i < 7; i ++) {
		ds_echo (ds_template_day_row(ds_daynames[i]));
	}
	// Make a date object.
	var ds_dc_date = new Date();
	ds_dc_date.setMonth(m - 1);
	ds_dc_date.setFullYear(y);
	ds_dc_date.setDate(1);
	if (m == 1 || m == 3 || m == 5 || m == 7 || m == 8 || m == 10 || m == 12) {
		days = 31;
	} else if (m == 4 || m == 6 || m == 9 || m == 11) {
		days = 30;
	} else {
		days = (y % 4 == 0) ? 29 : 28;
	}
	var first_day = ds_dc_date.getDay();
	var first_loop = 1;
	// Start the first week
	ds_echo (ds_template_new_week());
	// If sunday is not the first day of the month, make a blank cell...
	if (first_day != 0) {
		ds_echo (ds_template_blank_cell(first_day));
	}
	var j = first_day;
	for (i = 0; i < days; i ++) {
		// Today is sunday, make a new week.
		// If this sunday is the first day of the month,
		// we've made a new row for you already.
		if (j == 0 && !first_loop) {
			// New week!!
			ds_echo (ds_template_new_week());
		}
		// Make a row of that day!
		ds_echo (ds_template_day(i + 1, m, y));
		// This is not first loop anymore...
		first_loop = 0;
		// What is the next day?
		j ++;
		j %= 7;


	}
	// Do the footer
	ds_echo (ds_template_main_below());
	// And let's display..
	ds_ob_flush();
	// Scroll it into view.
	ds_ce.scrollIntoView();
}

// A function to show the calendar.
// When user click on the date, it will set the content of t.
function ds_sh(t) {
	// Set the element to set...
	ds_element = t;
	// Make a new date, and set the current month and year.
	var ds_sh_date = new Date();
	ds_c_month = ds_sh_date.getMonth() + 1;
	ds_c_year = ds_sh_date.getFullYear();
	// Draw the calendar
	ds_draw_calendar(ds_c_month, ds_c_year);
	// To change the position properly, we must show it first.
	ds_ce.style.display = '';
	// Move the calendar container!
	the_left = ds_getleft(t);
	the_top = ds_gettop(t) + t.offsetHeight;
	ds_ce.style.left = the_left + 'px';
	ds_ce.style.top = the_top + 'px';
	// Scroll it into view.
	ds_ce.scrollIntoView();
}

// Hide the calendar.
function ds_hi() {
	ds_ce.style.display = 'none';
}

// Moves to the next month...
function ds_nm() {
	// Increase the current month.
	ds_c_month ++;
	// We have passed December, let's go to the next year.
	// Increase the current year, and set the current month to January.
	if (ds_c_month > 12) {
		ds_c_month = 1; 
		ds_c_year++;
	}
	// Redraw the calendar.
	ds_draw_calendar(ds_c_month, ds_c_year);
}

// Moves to the previous month...
function ds_pm() {
	ds_c_month = ds_c_month - 1; // Can't use dash-dash here, it will make the page invalid.
	// We have passed January, let's go back to the previous year.
	// Decrease the current year, and set the current month to December.
	if (ds_c_month < 1) {
		ds_c_month = 12; 
		ds_c_year = ds_c_year - 1; // Can't use dash-dash here, it will make the page invalid.
	}
	// Redraw the calendar.
	ds_draw_calendar(ds_c_month, ds_c_year);
}

// Moves to the next year...
function ds_ny() {
	// Increase the current year.
	ds_c_year++;
	// Redraw the calendar.
	ds_draw_calendar(ds_c_month, ds_c_year);
}

// Moves to the previous year...
function ds_py() {
	// Decrease the current year.
	ds_c_year = ds_c_year - 1; // Can't use dash-dash here, it will make the page invalid.
	// Redraw the calendar.
	ds_draw_calendar(ds_c_month, ds_c_year);
}

// Format the date to output.
function ds_format_date(d, m, y) {
	// 2 digits month.
	m2 = '00' + m;
	m2 = m2.substr(m2.length - 2);
	// 2 digits day.
	d2 = '00' + d;
	d2 = d2.substr(d2.length - 2);
	// YYYY-MM-DD
	return y + '-' + m2 + '-' + d2;
}

// When the user clicks the day.
function ds_onclick(d, m, y) {
	// Hide the calendar.
	ds_hi();
	// Set the value of it, if we can.
	if (typeof(ds_element.value) != 'undefined') {
		ds_element.value = ds_format_date(d, m, y);
	// Maybe we want to set the HTML in it.
	} else if (typeof(ds_element.innerHTML) != 'undefined') {
		ds_element.innerHTML = ds_format_date(d, m, y);
	// I don't know how should we display it, just alert it to user.
	} else {
		alert (ds_format_date(d, m, y));
	}
}

// And here is the end.

// ]]> -->
</script>


  <div id="corps">
           <h1 class="Style1">Ajout d'un avion  </h1>
       
           <p>
<form action="modiav.php?etat=ajouter" method="post">
<table width="627" border="0" cellspacing="0" cellpadding="0">
  <tr>
    <td width="296" height="40"><span class="Style1">Indicatif:  </span><span class="Style2">---------</span> 
             <?php
                 $con=mysql_connect("localhost","root","");
                 $db=mysql_select_db("avion");

                 $sql=mysql_query("SELECT indicatif FROM 'fiche_avion'");

   ?>
      <select name="ident">
        <option></option>
        <?php while($row=mysql_fetch_array($sql))
     { 
  
       echo '<option value="'.$row['indicatif'].'">'.$row['indicatif'].'</option>';

     }
   ?>
      </select>   </td>
    <td width="331"><label><span class="Style1">Type :</span><span class="Style2">------------- </span> 
          
          <input type="text" name="type"/>
    </label></td>
    </tr>
  <tr>
    <td height="39"><span class="Style1">Date de Creation:
      <input onclick="ds_sh(this);" name="datte"  style="cursor: text" />
    </span></td>
    <td><label></label>
    </span><span class="Style1">Date de réception:
    <input onclick="ds_sh(this);" name="datte4"  style="cursor: text" />
    </span></td>
    </tr>
  <tr>
    <td height="47"><span class="Style1">N_Epg :</span><span class="Style2">----------</span>
        <input type="text" name="nepg" />
    </td>
    <td><span class="Style1">N=° serie :</span><span class="Style2">--------</span> 
        <input type="text" name="nserie"/>
    </td>
  </tr>
  <tr>
    <td height="47"><span class="Style1">Numero d'usine :</span><span class="Style2">-</span> 
        <input type="text" name="nusine"/>
    </td>
    <td><span class="Style1">N=°Bord :</span><span class="Style2">---------</span>
        <input type="text" name="nbord" />
    </td>
  </tr>
  <tr>
    <td height="47"><span class="Style1">1er_RG :</span><span class="Style2">---------</span>
        <input onclick="ds_sh(this);" name="datte1"  style="cursor: text" />
    </td>
    <td><label><span class="Style1">2eme_RG :</span><span class="Style2">--------</span>
          <input onclick="ds_sh(this);" name="datte2"  style="cursor: text" />
    </label>      </td>
  </tr>
  <tr>
    <td height="47"><label><span class="Style1">P1er_RG :</span></label>
     </span><span class="Style2"> -----</span>

        <textarea name="prgtext"></textarea></td>
    <td><span class="Style1">P2eme_RG :</span><span class="Style2">-------</span>
        <textarea name="prgtext2"></textarea>
    </td>
  </tr>
  <tr>
    <td height="47"><span class="Style1">3eme_RG :</span><span class="Style2">------</span>
        <input onclick="ds_sh(this);" name="datte3"  style="cursor: text" />
    </td>
    <td><label><span class="Style1">P3eme_RG :</span><span class="Style2">-------</span>
          <input type="text" name="prg3" />
    </label></td>
  </tr>
  <tr>
    <td height="47"><span class="Style1">Potentiel vie :</span><span class="Style2">---</span> 
        <textarea name="ptvie"></textarea>
    </td>
    <td><label></label></td>
  </tr>
  <tr>
    <td height="47">&nbsp;</td>
    <td><input type="submit" name="send" value="VALIDER" /></td>
  </tr>
</table>


</form>
</div>

2) Ou exécuter les requêtes sql de mise a jour

<?php
include("connexion.php");
session_start(); 
// ajouter 
if(isset($_GET['etat'])){
$etat = $_GET['etat'];


switch($etat){

	case "ajouter":
	############### AJOUTER un NOUVEAU Client #######################
	
 $va1=$_POST['ident'];
$_SESSION['identifient'] = $va1;
 $va2=$_POST['type'];
 $va3=$_POST['nepg'];
 $va4=$_POST['nserie'];
 $va5=$_POST['nbord'];
 $va6=$_POST['nusine'];
 $va7=$_POST['prgtext'];
 $va8=$_POST['prgtext2'];
 $va9=$_POST['prg3'];
 $va10=$_POST['ptvie'];

$date = $_POST['datte'];

 $date1 =$_POST['datte1'];

 $date2 =$_POST['datte2'];

 $date3 =$_POST['datte3'];		
 
 $date4 =$_POST['datte4'];	

 $requet = "UPDATE 'avion'.'fiche_avion' SET 'type' = '$va2',
'N_usine' = '$va6',
'mise_service' = '$date',
'reception' = '$date4',
'N_EPG' = '$va3',
'N_serie' = '$va4',
'N_bord' = '$va5',
'1er_RG' = '$date1',
'P1er_RG' = '$va7',
'2eme_RG' = '$date2',
'P2eme_RG' = '$va8',
'3eme_RG' = '$date3',
'P3eme_RG' = '$va9',
'Pvie' = 'update3' WHERE 'fiche_avion'.'indicatif' = '$va1';";

if(mysql_query($requet))
{
header("location:modifavio.php?status=success");
}
	}
	break;
	
	
	



}

?>

mais sa ne marche pas quand je clique sur le boutton valider il me reponds page web introuvable et il n'y a aucune modification dans la base de données
et dans l'url j'ai ça
http://127.0.0.1:8080/arme/modiav.php?etat=ajouter
se qui veut dire qu'il est dans la page d'execution des requetes et que sa ne marche pas alors que j'ai essayer la requete directement sur le sql de phpmyadmi et ça marche je ne sais plus quoi faire j'ai rien compris .
merci de votre aide